How Temporary Hit Points Work in D&D 5e (With Examples)

Last Updated on March 26, 2023

Combat is an integral part of the D&D 5e experience. Our characters get to fight against all sorts of fantastic creatures and come out feeling like heroes of legends. Of course, a lot goes into understanding how that combat works. Today, we’re looking at just one small part of 5e’s combat mechanics, temporary hit points, so that you can be better prepared to fight anything from a dragon to an army.

What Are Temporary Hit Points in D&D 5e?

Temporary hit points are a pool of hit points that exist to protect you from taking actual damage in D&D 5e. Normally, when you get hit by an attack, you take whatever damage is rolled. With temporary hit points, that damage is first applied to your temporary pool and anything left over gets applied to your actual hit points.

Let’s look at an actual example. You have 20 hit points and take 5 points of damage, which brings you to 15 current hit points. This is a normal combat damage calculation, and it’s as simple as subtraction. 

If instead you’ve been given 4 hit points from some source, the math looks a bit different. Now, you’ll fully deplete your 4 hit points and have 1 point of damage remaining. This 1 point gets taken from your hit points and you now have 19 current hit points.

How Long Do Temporary Hit Points Last?

Temporary hit points generally last until they are depleted or until you finish a long rest. Of course, certain effects may cause them to end sooner or may put a specific duration on the hit points themselves.

Let’s look at a couple of examples. We’ll be looking at the Sword of Life Stealing and the Potion of Heroism.

The Sword of Life Stealing reads as follows: “When you attack a creature with this magic weapon and roll a 20 on the attack roll, that target takes an extra 10 necrotic damage if it isn’t a construct or an undead. You also gain 10 temporary hit points.”

Naturally, we only really care about the 10 temporary hit points. This is our simple example since the source of our temporary hit points doesn’t add any extra contingencies. With this sword’s temporary hit points, we keep them until they are depleted or until we get a long rest in.

On the other hand, the Potion of Heroism reads as follows: “For 1 hour after drinking it, you gain 10 temporary hit points that last for 1 hour. For the same duration, you are under the effect of the bless spell (no concentration required).”

This text is a bit redundant, but it makes it very clear that our temporary hit points only last for 1 hour. Now, this isn’t in place of the rules we’ve already acknowledged. Instead, it’s just another option, and our temporary hit points disappear when we take a long rest, when they are depleted, or when an hour has passed, whichever happens first.

Temporary Hit Points From Multiple Sources

Probably the biggest mistake new players and DMs make when dealing with temporary hit points arises when a character would receive them from multiple sources. A character can only benefit from temporary hit points from one source. 

This means that if I drank a Potion of Heroism on one turn and then rolled a 20 with my Sword of Life Stealing on the next turn, I wouldn’t end up with 20 temporary hit points.

So, if temporary hit points don’t stack, what do we do? Well, we simply take whichever source offers us more temporary hit points. If the same situation occurred but we took 3 damage to our potion’s temporary hit points, the sword is going to essentially restock us back to 10. 

If two sources offer the same amount of temporary hit points, we get to choose which one to keep. Normally it won’t matter, but if we have a choice between a pool of hit points that lasts for 1 hour and a pool of hit points that only abides by normal rules, we’ll go for the normal rules.

Temporary Hit Points and Concentration

The last topic we’re going to cover is one that’s still open for debate. Okay, technically everything is open for debate since we can decide to roll with whatever rulings we want, but this one is an especially dicey scenario. How do temporary hit points affect concentration?

If you aren’t aware, concentration is a part of casting spells in 5e that allows spells to last for a certain duration at the expense of, well, a caster’s concentration. There are plenty of rules to go along with it, but the relevant one is that casters have to make a saving throw to keep their concentration when they take damage. 

If we go extremely literal and use the RAW (rules as written) approach, we might cite the PHB to say that temporary hit points are “a buffer against damage.” With this mindset, we would only consider damage dealt if they fully depleted our temporary hit points and ended up affecting our current hit points.

Jeremy Crawford, a game designer for WotC, has stated that “When temporary hit points absorb damage for you, you’re still taking damage, just not to your real hit points.” This means we would make a concentration saving throw even if our current hit points aren’t affected.

Neither of these is correct. Instead, they’re options for you to consider and decide on at your table. Having a house ruling is important because you truly never know when this might come up.

Final Thoughts

Temporary hit points are a fun way to keep your characters out of harm’s way, but they’re still game mechanics. Understanding how they work is essential to using them in D&D 5e. Once you do though, you’ll never have to worry about them again and they can just become another piece of enjoying this game.