Simple Q&A D&D 3.5 (by RAW) XXI

[Math_Mage]

Q 526

Can you use Deflect/Snatch Arrows on an attack that misses your AC? Put another way, are Deflect/Snatch Arrows used before or after the attack roll?

Deflect Arrows [General]
Prerequisites

Dex 13, Improved Unarmed Strike.
Benefit

You must have at least one hand free (holding nothing) to use this feat. Once per round when you would normally be hit with a ranged weapon, you may deflect it so that you take no damage from it. You must be aware of the attack and not flat-footed.

Attempting to deflect a ranged weapon doesn’t count as an action. Unusually massive ranged weapons and ranged attacks generated by spell effects can’t be deflected.