How Much Does a First Class Letter Weigh?

If you’re wondering how heavy a letter can be for a first class stamp, you’ve come to the right place.

The USPS gives mailers some wiggle room when it comes to how heavy first class letters can be…but if your letter is heavy, you may need to ship it.

3.5 ounces is the maximum for how heavy a first class letter can be

3.5 ounces is the maximum for how heavy a first class letter can be

First class letters can weigh as little as 3.5 ounces per mail piece.

If you need to send papers or documents that weigh more than 3.5 ounces, a good strategy is to divide your mail into separate, multiple envelopes with their own stamps.

Learn more about the difference between mailing and shipping.

The amount of first class (aka “permanent”) stamps you need to send a letter depends on the weight of your letter.

As a rule of thumb, one first class stamp represents one (1) ounce of postage for sending mail.

Therefore, if your letter weighs two (2) ounces, you need two Forever stamps.

If your letter reaches the maximum of 3.5 ounces, the USPS will require a total of four Forever stamps, since that extra half-ounce needs its own postage stamp to cover it.

Currently, the Forever stamp costs 58 cents.

You use these stamps to send letters via First Class Mail, but keep in mind that the USPS increases the cost of the stamps each time.

However, once you buy it, you can literally use it forever!

That means you can buy a Forever stamp today for 58 cents and use it ten or fifteen years down the road to send a letter with first class mail.

You can find rolls of Forever stamps at many different places, including some drug stores around town, your local post office, and of course, the USPS website.

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