5e Rogue Question: Sneak attack

This one came up over on BGG, with the same Opportunity Attack guy no less.



Question to put to those here.



When would you read Sneak attack with Two Weapons as being declared? Before you make the attack? Or after?



The question came up that by the rules wording you can make your first attack and if it misses, try for sneak attack with your second. Or if the first attack hits, call that it wasnt a sneak attack and reserve it for the second?



It doesnt quite sound right. But the wording of Sneak Attack just says.

Quote:

Once per turn, you can deal an extra 1d6 damage to one creature you hit with an attack if you have advantage on the attack roll. The attack must use a finesse or a ranged weapon.

If I am reading that right then yes you can wait to declare it till you know the hit is a success or not?

5e Rogue Question: Sneak attack