How much postage for a 3.7 oz large envelope?

The postage for a 3.7 oz large envelope within the United States typically falls under the First-Class Mail category. As of my last update, the cost for a large envelope weighing up to 4 oz is generally around $1.16. However, rates can vary based on factors like the destination or additional services requested, so it's always best to check the latest rates on the USPS website or at your local post office.