What are the margins required for Pantone Envelopes?

A minimum of .25" or 1/4" should be allowed on at least one edge (ideally the top edge where the flap is), as this is the margin that is required for the press to actually grip the envelope. The other edges should have a minimum of 1/8" or .125", so that any slight variations in the size of the envelopes or position of the printing will not be noticeable.