Which type of postage stamp allows you to send mail without expiration?

The type of postage stamp that allows you to send mail without expiration is the Forever stamp. These stamps enable the sender to mail a one-ounce letter at the current first-class mail rate, regardless of future rate increases. This means that even if postage prices rise in the future, the Forever stamp remains valid, thereby offering a convenient and cost-effective option for mailing letters over time.

This is particularly advantageous for individuals who want to stock up on stamps, knowing they won't lose value. Commemorative stamps, standard stamps, and seasonal stamps may have specific purposes or limited availability; they may also be subject to expiration based on price changes or specific uses, unlike the Forever stamp which maintains its validity as long as they are in good condition.