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.

20 cents, up from 20 cents in 2020. Padded Flat Rate Envelope $8.75 Commercial Base $9.30 at Post Office & Online Legal Flat Rate Envelope $8.45 Commercial Base $9.00 at Post Office & Online Small ...