What is a standard business size envelope? A standard envelope for business correspondence is a regular envelope. A popular #10 envelope measuring 4 1/8" by 9 1/2" is included in this product line.

What size envelope should be used to mail a standard size business letter? The most common type of business envelope is the regular envelope. A popular #10 envelope measuring 4 1/8" by 9 1/2" is ...