Sneak Attack on 2nd attack

Hi all,

Quick question, I have an Assassin Rogue (assassinate feature) which has Adv against enemies that have not yet taken a turn in combat.
I also have Crossbow Expert...

If my first attack kills an enemy, does my crossbow expert shot have sneak attack on the 2nd guy since I have Adv on him due to him not yet taking a turn.
Or does Sneak attack have to be used on the first attack?

Thanks in advance

You can use it once per turn. So if you decide not to use it on your first attack (note, you shouldn't find out if the damage without sneak attack is enough to kill or not before you decide) then you can use it on the second attack. Inversely, if you DO decide to use it on the first attack then you cannot use it on the second.

Note that you only need to choose to apply sneak attack after you have hit a target - generally you would most likely use this the first time on a turn that you successfully hit an enemy, rather than not using it and hoping that your second attack during that same turn is also a hit.

Note that the crossbow feat is irrelevant, other than it providing you with a second attack on the same turn.

Thanks folks.
Nice and quick clarification :)

That all being said you dont have to declare before the attack is rolled that im using Sneak Attack? in the case for dagger mastery (nick) 2 attacks one round.. so if the first dagger misses Id still have another attack in that same round that i could apply Sneak Attack to? its a current table issue..

Quote from badwhiskey >>

That all being said you dont have to declare before the attack is rolled that im using Sneak Attack? in the case for dagger mastery (nick) 2 attacks one round.. so if the first dagger misses Id still have another attack in that same round that i could apply Sneak Attack to? its a current table issue..

You do not have to "declare that you're using Sneak Attack" before the attack is rolled; that's not a thing. The text of the Sneak Attack features says that you use it to deal extra damage "to one creature you hit with an attack". Since it is explicitly defined as something that only applies to an attack that hits, you can't decide whether to use it or not until you know that the attack has hit.