Eldritch Knight Spell Guide For D&D 2024 (5.5e)

Analysing the best spell options for this magical fighter subclass.

The eldritch knight is a fighter subclass that gets a limited repertoire of spells. They can cast spells up to 4th level, earning them the title of a 1/3 caster.

While tacking spellcasting on to a fighter might ordinarily create a conflict between choosing to cast spells or attacks (and that conflict to some extent, remains), the eldritch knight does manage to accomplish both at the same time to some extent. This is especially the case with the updated 2024 subclass which has a much more seamless approach to merging those abilities.

Below, I’ve gone through all the spells available to the eldritch knight (which are cantrips and level 1-4 spells from the Wizard’s spell list), rated their effectiveness for an and provided some tips and insight around them. The recommendations below are geared specifically towards an eldritch knight meaning some spells that are great for other classes, may not score as well for an eldritch knight with the opposite also being true.

Considerations

Eldritch knights are a little unique among spellcasters with some interactions to be aware of:

Replacing attacks with cantrips – An eldritch knight can replace one of their attacks from the attack action with the casting of a cantrip. It’s important to be aware that cantrips increase in power more than a single attack does. This means that as cantrips become more powerful than a single attack (usually at level 5), it makes sense to combine these so you get an extra powerful attack action.
Is it worth casting more than making an attack? – One way to determine the effectiveness of a spell and whether it’s worth taking, is by comparing how much damage it can cause compared to your attack action. Of course, some spells are intended for more than just killing, but this can help with assessing the value of many combat spells.
Eldritch strike – Like the arcane trickster, eldritch knights have a method for making foes worse at resisting saving throw spells. At level 10 they can cause disadvantage on their next spell saving throw after hitting an enemy. This allows you to use attacks then follow up with saving throw spells the next turn. Or for a more fluid approach, you can take a cantrip like toll the dead or thunderclap that requires a saving throw, and use that as part of your attack action.

Cantrips

Psi warrior fighter DND 2024 — Fighter: Wizards of the Coast

Acid splash (4/5) – You only need to hit 2+ enemies to make this do more damage than any other cantrip. Essentially it’s worse than most cantrips against 1 enemy, but better against multiple enemies.
Blade ward (4/5) – Usually, I don’t favour this spell as it takes an action, concentration and is being used by a spellcaster that shouldn’t be getting attacked a lot. But the eldritch knight removes a lot of these issues by only expending a single attack to cast this (eventually) and will likely be attacked a lot. You also may not need to concentrate on many spells depending on your approach.
Chill touch (4/5) – If you plan on playing a melee eldritch knight, then you’ll want a melee spell attack. This one’s pretty good at 1d10 damage and stops your opponent healing. Keep spamming this to frustrate the enemy cleric.
Dancing lights (3/5) – Better than having to carry a torch around in the dark if you don’t have darkvision.
Elementalism (1/5) – Maybe there are cool effects others can work out that this spell can do, but to me, it all just seems like showmanship.
Fire bolt (3/5) – It lacks a special effect like chill touch and is a ranged spell attack so only for when making ranged attacks. You’re a fighter though, so likely needed in melee range most of the time. Decent cantrip for ranged attacks though.
Friends (2/5) – If you’re up against a lot of social situations, this can make them a fair bit easier. Unfortunately, it’s limited to a minute and only to non-hostile humanoids making its scope a bit tricky to make work.
Light (3/5) – Put down a weapon, cast light on it, then pick it up. Now you’ve got a torch without having to use a spare hand. Good for those without darkvision. Sadly you can’t just touch an invisible creature’s armor they’re wearing and cast this to reveal them, that would be a bit powerful for a cantrip.
Mage hand (4/5) – Great for some out of combat utility. Need to grab the key to your jail cell or pull the handle on the probably trapped door. Just use your mage hand!
Mending (2/5) – This one can be really useful, or not useful at all. It’s just too situational to be reliably of worth.
Message (3/5) – The range is a bit limiting, but if you’re split up and need to communicate, this is a good way to do it. No spell slots needed.
Mind sliver (4/5) – Combine this with your eldritch smite for really reliable saving throw spells, albeit with weaker damage.
Minor illusion (5/5) – Really useful and versatile illusion, great for adding some utility to your repertoire.
Poison spray (4/5) – Your highest damage for a ranged spell attack. Just be aware that the damage type is also one of the most highly resisted.
Prestidigitation (3/5) – I don’t think I’m as enamoured with this spell as many others, but it can be a useful utility spell if you’re creative enough. I’d prefer minor illusion and/or mage hand, but this can be handy too.
Ray of frost (3/5) – Good if you want to slow enemies down. You can actually combine this with the slow weapon mastery property to reduce movement by 20ft. I’d prefer the higher damage of other cantrips personally.
Shocking grasp (4/5) – Like chill touch but you stop opportunity attacks instead. Useful if you need to move around in combat.
Thunderclap (4/5) – Probably the better of the AoE cantrips for a fighter as you’re more likely to be in melee range. Just need to hit 2+ enemies to make this better damage than other cantrips.
Toll the dead (4/5) – Your best option for a ranged spell attack as it’s high damage and requires a saving throw instead of a spell attack. Not only does this mean you can cast it without disadvantage while next to an enemy, but it can also benefit from your eldritch smite for more reliable damage.
True strike (4/5) -Because you can replace a weapon attack with a cantrip, you can use this to have a cantrip use your weapon attack (with enhancements). Yes, that does sound confusing but an eldritch knight with a great sword will outperform on damage most cantrips other than poison spray and toll the dead, but has a bonus of dealing radiant damage, allowing weapon mastery uses and letting you use a magic weapon for the attack if you have something nice and juicy!

Level 1 spells

Alarm (3/5) – Making sure you aren’t surprised by an intruder is decent, but situational. It kind of depends on how your DM approaches rests and similar situations (and whether they like to ambush you). It’s a ritual so won’t eat into your precious spell slots at least.
Burning hands (3/5) – You’ll need to hit 3+ enemies for this to do more damage than your standard attacks (if you have 2 attacks). Decent enough option for crowds.
Charm person (3/5) – Pretty good if you’re sneaking about and need to get a guard or something else on side.
Chromatic orb (5/5) – The damage here is decent and the ability to change damage types means you should be able to avoid resistances. What makes this even better is your ability to potentially hit additional targets. You’ve got a 34% chance of rolling a double, but if you upcast this, the probability gets higher becoming 59% at level 2, 79% at level 3 and 92% at level 4. Plus you can have it bounce as many times as the level it’s cast at. This plays absolute havoc on whether it’s worth casting instead of taking the attack action! As a level 1 spell though, it will average 13.5 damage per target. With it bouncing 34% of the time, it should average 18.1 damage. This can quickly be overtaken by 2 attacks at level 5 with a greatsword. But by level 7, you can upcast this as a level 2 spell making it even more powerful. You can see exactly how powerful in my chromatic orb guide.
Color spray (2/5) – Blinding multiple enemies with a single spell is decent, but it’s only for one turn.
Comprehend languages (2/5) – It’s rare that not understanding a language would be a blocker to your game progression. And if it is, your DM probably needs to come up with better challenges.
Detect magic (4/5) – Someone needs this in the party and as it can be cast as a ritual, you don’t need to eat into precious spell slots.
Disguise self (3/5) – Great for social encounters and some subterfuge, though that’s not normally what a fighter gets involved in.
Expeditious retreat (2/5) – Retreating is rare, and having to be consistently faster than your enemy is even rarer.
False life (3/5) – Decent number of temporary hit points. You can cast in preparation for a battle too so no need to expend your action during combat.
Feather fall (4/5) – Really situational, but really useful if you ever do need it.
Find familiar (5/5) – Really useful for all sorts of things including the help action, sneaking around and getting places you can’t. You can also cast touch spells through it, like chill touch.
Fog cloud (3/5) – Lots of uses for heavily obscuring an area with fog.
Grease (3/5) – Really good in narrow areas like dungeons, especially if you want to fight enemies from a distance or stop them in the grease in melee combat giving them the chance of constantly slipping.
Ice knife (2/5) – If you want to cause a small AoE amount of damage, acid splash will do the same amount of damage other than the initial 1d10 to the target by level 5.
Identify (1/5) – You can usually work out what a magic item is without using a spell slot.
Illusory script (1/5) – It’ll be rare to find a use for this. At least it can be cast as a ritual, but feels like a big waste of a prepared spell.
Jump (3/5) – An extra 20ft of movement for a bonus action each turn of combat with no concentration required is decent. Or you can use it to jump across long distances or up buildings. Can be useful, especially at low levels when flight is harder to come by.
Longstrider (2/5) – Mostly you need extra speed in combat so unless you’re expecting multiple encounters very close together, this feels like a worse version of jump, that also doesn’t let you jump really far. Plus it takes up an action.
Mage armor (2/5) – Heavy armor can do better than this. Really only for times when you don’t want clunky armor ruining your stealth or if you’re a dexterity build.
Magic missile (3/5) – The damage is worse than your attacks, and that gap widens as you progress in levels, but it is an automatic hit and can target multiple enemies. If you absolutely must hit, this is the spell you want, but don’t expect it to do much to a big sack of hit points!
Protection from evil and good (4/5) – A little situational, but there’s a wide range of creatures that this protects you from so you’re bound to come across them at some point.
Ray of sickness (2/5) – An average of 9 damage and the poisoned condition for a turn is not strong enough I think compared to your other options.
Shield (4/5) – If you plan on focusing on melee combat, you’re likely to take a beating. This is a defensive way of using your reaction and should keep you in the game longer.
Silent image (4/5) – A better version of minor illusion, but at the cost of a spell slot.
Sleep (4/5) – It’s a small AoE, but if you can catch multiple enemies in this, the odds of success increase a lot and can be fairly substantial. Be aware though that the saving throw on the 2nd turn won’t be taken with disadvantage, even if you were using eldritch smite on the first turn.
Spellfire flare (3/5) HoF – In terms of raw damage, the dice are equal to inflict wounds, but inflict wounds will deal half damage on a successful saving throw, this just misses. However, this is ranged (inflict wounds requires touch) and it ignores half and three quarters cover. Where it gets interesting is with upcasting as it creates separate blasts like scorching ray. It has one less blast than scorching ray, but the damage at level 2 is slightly higher, and because we’re dealing with d10s instead of d6s, it scales better at even higher levels.
Tasha’s Hideous Laughter (3/5) – Sleep is a better option here as you can affect multiple enemies. Still reasonably effective if you have a high enough intelligence or have used eldritch smite, especially as allies can’t just kick your target awake.
Tenser’s floating disk (1/5) – Far too situational to be wasted on your meagre spell supply.
Thunderwave (4/5) – An average of 9 damage per target. You only need to hit 2 enemies to make this deal as much damage as chromatic orb (at level 1), 3 and you exceed that. Normally, this is a challenging spell for spellcasters due to the need to be isolated in the middle of enemies, but that’s where eldritch knights thrive, making this a really good fit.
Unseen servant (3/5) – This is a decent spell, but if you want this kind of utility, I’d probably suggest taking mage hand instead due to your limited spell slots.
Wardaway (2/5) HoF – The damage isn’t big but the restrictions are kind of limiting. Half speed and lose an action or a bonus action is annoying, but this is only for one turn at most. My issue with this is that the damage isn’t great and neither is the debuff. If I want to nullify, then sleep or Tasha’s hideous laughter are better. If I want damage, then magic missile, spellfire flare or chromatic orb are better. I’d rather do one thing well than 2 things badly.
Witch bolt (2/5) – The initial damage is less than what you can deal with weapon attacks by level 5. You do get extra damage each turn after, but you must use your bonus action, concentration and this ends if the target runs round a corner or dies. I feel this is too high a cost for what this spell offers.

Level 2 spells

Alter self (3/5) – Kind of like disguise self with extras. If you’ve built to fight unarmed, you should have the unarmed fighting style already which gives your unarmed strikes 1d6 damage, but a swim speed is sometimes useful. The disguise elements are less restrictive than disguise self, which is mainly why you’re here.
Arcane lock (2/5) – There are uses for this, but it tends to be too situational
Arcane vigor (3/5) – An average of about 14 hp healed isn’t bad for a bonus action that might otherwise go unused. Enough to keep you fighting a little bit longer.
Augury (4/5) – With this being a ritual, you could really use it a lot, like at every important decision you make. The challenge you get is it could easily just be useless information you get or based on your DM’s expectations. It’s still a really powerful tool though.
Blindness/deafness (4/5) – Solid enough saving throw spells with the benefit of not requiring concentration elevating it a point.
Blur (4/5) – Strong defensive spell, though it gets less effective as enemies get better at hitting you, with disadvantage causing less of a problem for accurate creatures.
Cloud of daggers (2/5) – Unless you can block a 5ft wide corridor with this, it’s just a waste of a spell slot and you can save the spell slot and use sneak attack instead.
Continual flame (1/5) – There are other ways to create light without using a 2nd level spell slot. Yes I know it lasts forever, no that doesn’t change my opinion.
Crown of madness (3/5) – The challenge with this is you’ll need to maintain it using your action to continue its effects. This can be an acceptable sacrifice if you come across someone powerful, but lacking in the wisdom department. It’s a high action price, but worth it if you can make it work.
Darkness (3/5) – If you want a portable version of fog cloud, you could take this instead (maybe because you have something like blindsight or you just want to shroud yourself in darkness). Just cast it on a sword or something else easily portable. Otherwise, fog cloud has a similar, more stationary effect at a lower level spell slot.
Darkvision (3/5) – The best way to see in the dark if you don’t already have darkvision.
Death armor (5/5) HoF – Advantage on death saving throws is fine, but it’s the kind of buff you don’t really want to need (and often won’t need). The important bit here is the extra damage. The wording is once per turn the damage can be dealt, that means it can affect every enemy that makes a melee attack against the target. That damage can soon rack up, even if it is spread between multiple enemies. You can cast ahead of combat and it doesn’t require concentration making it an excellent buff! Just ask your allies to keep you healed up so you don’t go down while in the middle of enemies.
Deryan’s helpful homunculi (1/5) HoF – Essentially faster crafting. There’s an issue here though. This will cost you 100gp every time you use it and as it only lasts 8hrs, will only help for a single day of crafting (so you get through 2 days of crafting while they’re helping). Considering that anything worth crafting and spending an extra 100gp making is going to take several days at least to craft, this just seems like poor economics, especially considering you’re likely crafting for the cheaper gear anyway. This just seems like a pointless spell to me. However, there is perhaps a work around here. Using circle magic, you can use the supplant option with 2 other spellcasters to remove the material cost entirely. But you are reliant on circle magic rules being used at your table and 2 other spellcasters available to help.
Detect thoughts (3/5) – There are interesting ways to use this for both stealth and social situations, but taking advantage of it is a bit situational, depends on your DM’s generosity and can go wrong with that wisdom saving throw. As you likely can’t eldritch smite your target first, this can be a better spell on more dedicated spellcasters.
Dragon’s breath (3/5) – This is kind of like reusable burning hands for a whole combat that you can grant to someone else. If you’re going to be dealing with hordes, this will be better than your attack action. Or you could cast it on someone else with less precious attacks (like a familiar if you have one).
Elminster’s elusion (3/5) HoF – Decent magical protection that you can cast ahead of combat and with just a bonus action. It will consume your concentration, but if you’re up against spellcasters, this might well be worth the cost.
Enhance ability (4/5) – Usually best cast on an ally, help them with their skills checks as you’re not the best at these. A good option for difficult social and stealth situations.
Enlarge/reduce (3/5) – Decent buff or debuff. Works nicely on grapplers like monks (or yourself with the right build) so they can grapple larger things and do more damage (at the same time if they have the grappler feat). Or cast it against a high level enemy your party grappler wants to grapple.
Flaming sphere (2/5) – Like a slightly better version of cloud of daggers. It has a larger radius, affects creatures within 5ft on the first turn and can be moved with a bonus action instead of an action. The damage is a little lower though and it has to be rolled rather than teleported. Despite being better, it’s too low damage to consistently invest in.
Gentle repose (1/5) – Any creature important enough to aid with this spell, could usually have had something else cast to prevent it decaying too much. In fact, a cleric could already have had revivify for 2 levels at this point (for recent deaths) and gets raise dead in 2 more turns, making this largely redundant.
Gust of wind (2/5) – Decent for corridors, poor for small or large spaces. This makes it too situational to be regularly useful.
Hold person (4/5) – Solid save or suck spell. With eldritch smite too, this can be easier to make work.
Invisibility (4/5) – Great for stealth segments or getting the jump on enemies in the first round of combat.
Knock (3/5) – This is a spell you pick if you don’t have a rogue. Important if no one else can pick locks very well.
Levitate (3/5) – Useful for scaling tall buildings and scouting. You can also nullify an enemy to some extent with this, especially if they don’t have ranged options.
Locate object (2/5) – Theoretically, this can be useful as some kind of bug you can use to track an enemy. Can also help you find important items, but it’s also highly situational and you could easily go an entire campaign without having the chance to use this.
Magic mouth (1/5) – This can have it’s uses, but is also highly situational and relies on fairly uncommon circumstances to be useful.
Magic weapon (4/5) – More accuracy, slightly more damage and make your damage magical with just the use of a bonus action. There’s no concentration needed here either. Solid for a multi-attack warrior.
Melf’s acid arrow (2/5) – An average of 15 damage across 2 turns isn’t that great. At this level, you’ll already be doing more damage with your basic attacks. This only has the advantage of always doing at least some damage, but personally, I’d just upcast chromatic orb.
Mind spike (1/5) – The problem with this is the damage is low and you have to be able to see the creature to hit it and then nullify future invisibility attempts. Problem is, you often don’t know you’re going to face something that can turn invisible until it turns invisible. At best, this works against enemy rogues. There are better ways to tackle invisibility though.
Mirror image (3/5) – Blur is probably better at lower levels, but this probably works better at higher levels when enemies are more accurate.
Misty step (4/5) – Solid manoeuvrability spell that you can cast with your bonus action. Use it to reach the right places, extend your movement or retreat.
Nystul’s magic aura (1/5) – This is a bit niche in its application and is probably more of a DM’s tool than anything else. Really you’re trying to conceal a disguise or the true nature of an artefact or weapon. A lich could use it to pass as not being undead for instance. It’s highly circumstantial and rarely going to be of use.
Phantasmal force (3/5) – If you’re creative, you can do a lot of interesting things with this spell. False bridges, fake ground or holes are all possibilities as well as scary creatures.
Ray of enfeeblement (1/5) – The best enemies to cast this on (strong, melee brawlers) are likely the best at resisting this (constitution saving throw) making it a tad tricky. It still does something on a failure, but the issue you have is hold person will completely disable an opponent, this only partially does so, making it tough to recommend this over something better.
Rope trick (2/5) – Your mileage out of this probably depends on how often you need somewhere to suddenly hide in. But many of these scenarios are far too circumstantial to be of regular use.
Scorching ray (2/5) – About as good as your attack action by the time you get this and overtaken once you get 3 attacks. Hard to recommend unless you want to combine with conjure minor elementals, which you shouldn’t. That build is broken and I suspect most DMs will ban or adjust that option.
See invisibility (4/5) – At least someone in the party needs a way to deal with invisibility and this is probably one of the better low level options. This is even more handy now that the hide action grants the invisible condition.
Shatter (4/5) – Probably the best pre-level 3 AoE damage dealer. One of your best options at this level for dealing with crowds.
Spider climb (2/5) – This can be useful sometimes, but I’d probably just go for levitate over this. It’s more versatile and works better for gaining height.
Suggestion (4/5) – Time for some jedi mind tricks! It’s inferior to hold person at incapacitating enemies, but sometimes you need to have someone do something for you (like to grab the key to the jail cell you’re in). You’ll need to be careful at wording your instructions though.
Web (5/5) – Strong control spell. Will slow down multiple enemies and can restrain them too.

Level 3 spells

paladin — Eldritch knight: Wizards of the Coast

Animate dead (2/5) – Zombies and skeletons aren’t that great and probably won’t survive the whole 24hrs.
Bestow curse (2/5) – None of these effects are particularly strong. Yes, some of them will work continuously without future saving throws, but I’d still prefer blindness or Tasha’s hideous laughter.
Blink (1/5) – Normally, fighters want to be in the thick of combat, drawing enemy attacks from weaker members of the party. That makes this a poor choice for a fighter who will just disappear half the time. The flavour of it could be fun though, especially if you already have a lot of martials in your party, but you will have to sacrifice a turn of attacks to set this up.
Cacophonic shield (4/5) HoF – Like a slightly less damaging spirit guardians. The emanation’s range is smaller too but you get thunder resistance, ranged attacks have disadvantage against you and you cause deafened with it. These seem like decent trade offs and a great option for a fighter to grab something like spirit guardians. In fact, you’re probably the best subclass to be using this spell.
Clairvoyance (4/5) – There’s quite a lot of potential for information gathering with this spell, especially if you want to be privy to conversations not meant for your ears! It’s a bit situational though so you may not get loads of use out of it (then again, you could end up using it a lot).
Conjure constructs (1/5) HoF – This seems significantly worse than conjure animals (the same level equivalent spell). The range is worse, the damage is significantly worse (conjure animals can affect multiple creatures per round) and even the damage per hit is worse (3d6 Vs 3d10 for conjure animals). The temporary hit points also aren’t that much. For me, this is just a significantly inferior and underwhelming spell for this level.
Counterspell (3/5) – Preventing a nasty spell is great, but you don’t have a lot of spells slots so be selective in your use of this. Just be aware that while you might waste the caster’s action with this, the 2024 changes mean that the spell slot isn’t wasted so they could just cast the nasty spell again the next turn instead.
Dispel magic (5/5) – Really useful for ending nasty spell effects.
Fear (4/5) – Strong way to take a bunch of enemies out of the combat simultaneously, especially if you’re fighting large groups. You do have to get fairly close to the enemy for this one, but that’s not a problem for an eldritch knight.
Feign death (1/5) – It’s hard to understand under what niche circumstances this spell would be useful… Perhaps if you need to infiltrate a morgue…
Fireball (5/5) – Really strong damage dealing AoE spell. Best used in the first turn before you and your allies get in the way.
Fly (4/5) – Really useful utility spell. Can keep you safe(ish) in combat and helps you access hard to reach locations (which is great for sneaky character).
Gaseous form (4/5) – Strong exploration spell. Will get you places you might not ordinarily be able to get.
Glyph of warding (3/5) – This is a tricky one to rate. With preparation time, it’s a really great way to cause damage to an enemy without using up your action in combat. I believe there’s an exploit here, as concentration spells just last for the duration, without consuming your concentration it seems. So you could cast hold person using the glyph and then still have space to concentrate on haste or something similar. However, this spell is fairly situational as it relies on prep time and knowing an enemy is coming.
Haste (4/5) – A strong buff that can easily enhance yourself or an ally. An extra attacks, more speed, better AC and better saving throws all combine nicely.
Hypnotic pattern (5/5) – Strong method of nullifying multiple enemies in combat. I’d take this over fear as it’s got further range, a bigger AoE and does completely nullify enemies.
Laeral’s silver lance (2/5) HoF – Basically a weaker lightning bolt that also knocks prone. It has a slightly greater range than lightning bolt but quite a bit less damage. Unless you’re fighting down corridors, this probably isn’t a great option and I’m not convinced that prone is enough for the damage sacrifice.
Leomund’s tiny hit (3/5) – Basically a safe place to rest each night. You could also use it as a safety measure if you have preparation time for a combat. Essentially you set up the hut and then hop in and out of it, keeping you safe and giving you a place to hide. Just be aware of level 4+ spells that can penetrate the walls.
Lightning bolt (3/5) – Lines of enemies are harder to find than groups, but can happen in long corridors. Generally though, this tends to be weaker than fireball.
Magic circle (2/5) – This is generally quite challenging to use as it requires a 1 minute casting time. It also requires certain types of creatures making it far too situational.
Major image (5/5) – If you’re really creative, this can be amazing! Basically an enhanced minor illusion, it’s great for distractions and deception.
Nondetection (2/5) – This is way too situational to be of much use! It’s really for DMs to keep locations of important things extra secret. Yes, you could prevent your invisibility from being revealed, but it’s not common enough to face enemy spellcasters to make this regularly useful.
Phantom steed (2/5) – This isn’t a steed built for combat unfortunately as it fades as soon as it takes damage. It’s mainly for travel which can sometimes be convenient, but not that useful in game, especially as the party also need their own steeds to keep up.
Protection from energy (2/5) – A single resistance can be bypassed easily (by using a different damage type or targeting another character). The options of damage types are quite limited too. Situationally useful against certain creatures.
Remove curse (2/5) – Sometimes useful, but you could just be a bit more cautious about what magic items you use, or find a friendly cleric to help you. You’re too low on spells known to waste on this.
Sending (2/5) – A little too situational for regular usage. You only get one message too so it can be used for one piece of communication with others. A 3rd level spells slots is a big price to pay for a message that’s a couple of sentences long.
Sleet storm (3/5) – A more problematic version of fog cloud. Good for controlling the battlefield and nullifying enemy spellcasters a bit. It’s best in more confined spaces where enemies may be forced to travel through it.
Slow (4/5) – I prefer hypnotic pattern over this which completely nullifies an enemy rather than severely debilitating them. But this is still very good and has a larger area it can cover.
Speak with dead (4/5) – Really useful information gathering spell. How well it works partially depends on your DM. I find many players are quite trigger happy in killing rather than knocking unconscious enemies, this is some kind of insurance against that behaviour.
Stinking cloud (3/5) – Good control spell. Works best in confined spaces and for getting enemies in the places you want them to be. Poisoned is nastier with this spell, but only lasts a turn. Consider combining it with something that restricts movement like sleet storm, grease or web to really get enemies stuck.
Summon fey (3/5) – Solid summon with decent damage and utility. No need to use a bonus action to command it so this is preserved.
Summon undead (3/5) – Not quite as good as summon fey which has a few more options to help you out and does more damage. Decent enough, though it’s worth keeping in mind that by the time you get these summons, they may feel a bit underpowered compared to what enemies can do.
Syluné‘s viper (2/5) HoF – Those temporary hit points may not last long which could lead to an early end for the spell. A climb speed at this level isn’t that impressive and the damage is very weak considering it requires an action. Incapacitated is good, but you could instantly whack a group of enemies with that and more in a single turn with hypnotic pattern. This just doesn’t seem worth it.
Tongues (2/5) – It’s unlikely that this will be useful very often so not worth taking.
Vampiric touch (2/5) – This doesn’t deal enough damage or heal enough to make it worthwhile at the sacrifice of your multiple attacks. If you want some healing, arcane vigor is cast with a bonus action, will heal more hit points and only requires a level 2 spell slot.
Water breathing (2/5) – The need to breath underwater is rare, but can be very useful when needed. The problem here is it’s just too situational to be used often. I’ve gone whole campaigns where I’d never be able to use this. Maybe take if you’ll be involved in a nautical campaign.

Level 4 spells

Arcane eye (4/5) – Really good investigation spell that can let you spy on a location without setting foot inside.
Backlash (4/5) HoF – Solid damage reduction and retaliation. For comparison, hellish rebuke will deal 5d10 damage if upcast to this level (average 27.5 damage). Backlash will protect from an average of 14 damage and deal 14 damage back (with a better damage type). So I think they’re comparable in power.
Banishment (5/5) – Take an enemy out of combat for the duration while you deal with it’s friends. Hold person accomplishes a similar thing but this is better as there aren’t any repeat saving throws and many creatures have poor charisma. Use eldritch strike to make this more reliable.
Blight (2/5) – By the time you get this at level 19, the average damage of your attack action is higher than this. I also suspect an upcast chromatic orb would average a lot more damage too.
Charm monster (2/5) – I find this tough to recommend. You’re not necessarily gaining an ally for combat, even then, it’ll only hang around for an hour before knowing you magically influenced it. It has some niche application, but it’s not useful often enough.
Confusion (3/5) – This is like an unreliable hypnotic pattern. I prefer hypnotic pattern with it’s larger area of effect and greater reliability, but if you like chaos, this can sometimes cause enemies to attack each other.
Conjure minor elementals (5/5) – This is very powerful if you know what to do with it. An eldritch knight doesn’t have high enough spell slots for this to be properly abusable, but wizards can do devastating things with this at higher levels (RAW at least). Essentially, you want to keep casting spells with multiple attack rolls to maximise damage from the spell. I think the best you can do here is scorching ray upcast to level 3 for 4 rays (you only get 1 level 4 spell which is taken up by this spell). That means an extra 8d8 damage which on top of the 8d6 damage you were already dealing (and you can manage this 3 times per long rest). That considerably outperforms your attack action. On an eldritch knight, this is powerful, but not broken. On other spellcasters, it is broken, and personally, I’ll be restricting this spell in my games and suspect many DMs may do the same so maybe chat to your DM about how they want to handle this combination if it’s something you’re intending.
Control water (2/5) – You can do some fun, creative stuff with this spell, but your opportunities to do so are pretty rare so ends up too situational.
Dimension door (3/5) – Good for getting out of dungeons quickly or getting the jump on far away enemies. You may need to be a little creative, but as long as you can see, have seen or can precisely determine distance of the location, you can get there safely. Misty step is usually a sufficient teleport and can be cast as a bonus action, even if this has some interesting, extra utility.
Divination (3/5) – Can be a very useful information gathering spell and isn’t particularly situational. But it’s mileage depends on the generosity of your DM.
Evard’s black tentacles (4/5) – Very useful in confined spaces and restrained is a powerful condition, plus enemies will take some damage too.
Fabricate (2/5) – While it’s possible for this to be very useful, it’s very situational in nature and often won’t be particularly useful.
Fire shield (4/5) – Can be a great option on a martial warrior who should be prone to getting attacked a lot. Of course, tactically, enemies may just shift focus or start launching projectiles at you, but this could cause some problems if you’re getting in their face. The chill shield is better as it protects from fire damage which is more common than cold, while dealing cold damage which is resisted less often than fire damage.
Greater invisibility (5/5) – Disappear in combat and attack with advantage and be attacked with disadvantage.
Hallucinatory terrain (1/5) – This feels like it could be loads of fun, but I find that working out the practical use cases for this really challenging. Maybe I’m just not creative enough, but you’ve not got enough prepared spells to waste on such a rarely useful spells.
Ice storm (2/5) – The damage here isn’t particularly high and difficult terrain for a single turn isn’t that great either.
Leomund’s secret chest (1/5) – This is an expensive spell to keep something safe. Presumably you’re tough enough to protect your own things quite capably be level 19.
Locate creature (2/5) – Situationally useful if you need to track someone down, but unlikely to happen often enough to really justify.
Mordenkainen’s faithful hound (2/5) – Kind of like a better alarm with a bite. If you’re worried about invisible creatures or intruders during rests, it’s not bad, but this is your highest spell slot, it’s rarely actually going to attack, and you can deal with invisibility better with something like see invisibility at level 2 so this is hard to recommend.
Mordenkainen’s private sanctum (2/5) – This can be useful, but it’s too situational to regularly actually help, especially for your highest spell slot.
Otiluke’s resilient sphere (5/5) – Great way to nullify an enemy. The practical effects are the same as banishment but with a dexterity saving throw instead of a charisma saving throw. More creatures are better at dexterity than charisma so I’d favour banishment, but you could also use this as a protective shield in desperate situations. Or roll your enemy somewhere nasty before the time runs out.
Phantasmal killer (3/5) – Continuous damage means it takes about 2-3 turns to hit the levels your attack action will be at in damage. It does reduce the effectiveness of the enemy as well though and continuous eldritch strike can make the target more likely to fail subsequent saving throws.
Polymorph (5/5) – Effectively nullify an enemy, enhance an ally or gain some kind of utility benefit like flight. This is a really versatile spell!
Spellfire storm (3/5) HoF – Lower damage than fireball but it can prevent spells when cast in it’s area and does stick around. With teamwork, you could make some big damage happen here, but it’s tricky to have enemies in the area long enough to make it do more damage than a fireball.
Stone shape (3/5) – This is quite situational, but also, potentially quite useful. Bypass natural walls in a dungeon by simply shaping the stone and passing through them. Of course, you could just watch your DM have many 6ft thick walls in their dungeon, but that would be cruel to ingenuity.
Stoneskin (2/5) – Ordinarily a good range of damage resistances, but by 19th level (when you can access this), many creatures you fight will be using different or more varied damage types making this less effective.
Summon aberration (3/5) – It’s pretty decent, but with upcasting at higher levels, I’d say summon fey is better.
Summon construct (3/5) – Decent enough summon. I prefer the metal construct, but do think summon fey is a little better when cast at this level.
Summon elemental (3/5) – Slightly better damage, damage types and hp than most summons, but still stacks up closely in quality. The best summon for adaptable damage types.
Vitrolic sphere (4/5) – On a failed save, this is a little better than a level 4 fireball, but on a passed save, is a little worse. I’d be tempted to stick to fireball at level 3 as you can cast that at both levels (important as you only get 1 level 4 spell slot).
Wall of fire (4/5) – Can be a useful way to control the battlefield, separating, slowing and/or damaging your enemies.