If you’re wondering how heavy a letter can be for a First Class stamp, you’ve come to the right place. USPS gives mailers a little bit of wiggle room when it comes to how heavy First Class letters can be…but if your letter weighs too much, you may need to ship it.
Table of Contents
- 3.5 Ounces is the Maximum for How Heavy a First Class Letter Can Be
- Forever Stamps Cover the Cost of One Ounce for a First Class Letter
- USPS Requires an Extra Stamp for Additional Ounces After 1 Oz
- The Cost of Stamps
3.5 Ounces is the Maximum for How Heavy a First Class Letter Can Be
A First Class letter can only weigh up to 3.5 ounces per mail piece. If you need to send papers or documentation that weighs more than 3.5 ounces, a good strategy is to break up your mail into separate, multiple envelopes with their own stamps. Or, you could always ship it all together using a single Priority Mail Flat Rate Envelope!
Pro Tip: A lot of beginners accidentally mix up the terms “mailing” and “shipping” when, in fact, they describe two wildly different things. Learn more about the difference between mailing and shipping.
Forever Stamps Cover the Cost of One Ounce for a First Class Letter
One Forever First-Class Mail stamp represents the postage for sending one (1) ounce of mail. So, a forever First-Class stamp only buys you enough postage for a one (1 oz) ounce letter. Most letters and postcards weigh less than 1 ounce, though, and therefore require only one Forever Stamp. However, if your letter weighs more than that, you’ll need to pay for additional ounce stamps…and we get into that below.
USPS Requires an Extra Stamp for Additional Ounces After 1 Oz
Letters that weigh more than 1 ounce require additional ounce stamps on top of your first Forever Stamp. Here’s what we mean:
If your letter weighs two (2) ounces, you need one Forever stamp and one additional ounce stamp. If your letter weighs three (3) ounces, you’ll need one Forever stamp and two additional ounce stamps.
If your letter hits the maximum amount of 3.5 ounces, USPS will require a total of four stamps (one Forever and three additional ounce stamp), since that extra half-an-ounce needs its own postage stamp to cover it. Any piece of mail that weighs more than 3.5 will need to be shipped instead of mailed, and you can use USPS shipping services such as First Class Package or Priority Mail for that.
The Cost of Stamps
Currently, Forever stamps cost 63 cents each. You use these stamps to send letters via First Class Mail, but keep in mind that USPS raises the price of stamps every so often. However, once you buy them, you’re good to use them literally forever! That means you can buy a Forever stamp today for 63 cents, and use it ten or fifteen years down the line to send a letter with First Class Mail. Just make sure you don’t lose them!
Additional ounce stamps are cheaper than Forever stamps; currently, they are priced at 24 cents. If your letter is two ounces, the total cost to mail it will be 87 cents (one Forever stamp at $0.63 and one additional ounce stamp at $0.24).
You can pick up rolls of Forever stamps at a lot of different locations, including certain drug stores around town, your local Post Office, and of course, on the USPS website.