A standard domestic postcard needs exactly one postcard stamp. Postcard stamps pay the First-Class Mail postcard rate, a separate price that USPS always sets below the one-ounce letter rate, and they only work on cards between 3.5 × 5 inches and 4.25 × 6 inches.
That is the whole answer for a typical vacation card or save-the-date. The rest of this guide covers what the postcard rate is, how to tell whether your card qualifies for it, where to see today’s price, and where to buy postcard stamps singly or in bulk.
Key Takeaways
- One standard postcard takes one postcard stamp in the upper-right corner, with nothing else added.
- The postcard rate is its own First-Class Mail price, lower than the letter rate. USPS lists the current figure on its First-Class Mail page, and prices last changed on July 12, 2026.
- Only rectangular cards from 3.5 × 5 inches up to 4.25 × 6 inches, 0.007 to 0.016 inch thick, qualify. Bigger or thicker cards pay the letter rate.
- A letter Forever stamp also works on a postcard, but you pay the higher letter rate for it.
- Postcards to other countries need international postage. One Global Forever stamp covers a standard postcard to any country.
How Many Stamps Does a Postcard Need?
One. A standard postcard sent anywhere in the United States needs a single postcard stamp. You don’t stack a letter stamp on top of it, and you don’t need two postcard stamps. Put the stamp in the upper-right corner of the address side, the same spot you would use on a letter.
The one-stamp rule only holds while the card counts as a card under the USPS Domestic Mail Manual, section 101. Under those standards a card must be rectangular, 3.5 to 4.25 inches high, 5 to 6 inches long, 0.007 to 0.016 inch thick, and no heavier than 3.5 ounces. A card outside any of those limits is charged letter-size postage, so it needs a letter stamp instead. Large envelopes and thick packets follow their own rules, which our guide to how many stamps a large envelope needs works through.
What Is the Postcard Rate, and Where Can You See Today’s Price?
The postcard rate is the First-Class Mail price USPS charges for a single qualifying card. It sits below the price of a one-ounce letter because a card is smaller and lighter and has no envelope to process. A postcard stamp is printed for that rate, so it pays a card’s postage exactly instead of overpaying at the letter rate.
USPS changes mailing prices periodically. The most recent change took effect on July 12, 2026, and raised both the domestic postcard rate and the letter rate as part of an increase of about 4.8 percent across mailing services. Because the figure moves, we don’t print it here. The current postcard price is listed on the USPS First-Class Mail page and in the USPS announcement of the July 2026 prices.
The gap between the two rates matters most when you mail in volume. On one card it hardly matters. On a few hundred holiday cards or a small-business mailer, the postcard stamp is the cheaper option for every card. Letter postage works the same way, and our page on how much a book of stamps costs explains how letter stamps are packaged and sold.
| Mailpiece | Postage it needs | Qualifying size | Rate class |
|---|---|---|---|
| Standard postcard | 1 postcard stamp | 3.5 × 5 in to 4.25 × 6 in, 0.007–0.016 in thick | First-Class Mail card (lowest) |
| Oversized or thick card | 1 letter stamp | Over 4.25 × 6 in or over 0.016 in thick | First-Class Mail letter |
| Card over 3.5 oz | Flat-size postage | Card-shaped but over the weight limit | First-Class Mail flat |
| Postcard to another country | 1 Global Forever stamp | Standard size, up to 1 oz, rectangular | First-Class Mail International |
Can You Use a Regular Forever Stamp on a Postcard?
Yes. A letter Forever stamp is always worth the current one-ounce letter rate, which is more than the postcard rate, so USPS will deliver the card with no postage due. You just overpay by the difference between the two rates. On one card that’s trivial. On a big stack of cards it adds up.
It doesn’t work the other way. A postcard stamp only covers the postcard rate, so it can’t pay for a sealed letter. If you put one on an envelope, USPS treats the letter as underpaid and may return it to you or collect the shortfall from the recipient. Match the stamp to the mailpiece: postcard stamps on cards, letter stamps on letters. If you’re not sure whether a letter is still within one-ounce postage, our guide to how heavy a letter can be for one First-Class stamp covers the weight limits.
Where Can You Buy Postcard Stamps?
You can buy postcard stamps most places that sell postage, but not every outlet stocks them:
- The Post Office counter. Ask for “postcard stamps” by name, because clerks usually reach for letter Forever stamps first.
- The USPS Postal Store online. USPS lists its postcard-rate stamps in their own category and ships them to your door.
- Self-service kiosks in many Post Office lobbies, which sell postage after hours.
- Grocery stores, pharmacies and office-supply stores. Most sell books of letter stamps, but postcard stamps are hit or miss, so call ahead if you need them.
The ParcelPath USPS guides list where to buy every kind of USPS postage. For postcard stamps, the one tip that matters is to ask for the postcard denomination by name so you don’t walk out with letter stamps.
How Do You Buy Postcard Stamps in Bulk?
If you mail cards in quantity, such as a save-the-date run, a classroom project or a small-business mailer, buy postcard stamps in a coil or pane rather than one at a time. The USPS Postal Store sells its postcard stamps in multi-stamp formats, including coils that come on a roll so you can peel stamps off a strip. Postcard coils work the same way as letter coils, which our roll of stamps guide explains. The only difference is the rate printed on the stamp.
Very large commercial mailings can use presorted business prices instead of stamps, but those need a mailing permit and minimum piece counts, which is a different process from buying postage. For most people, a coil of postcard stamps is the practical bulk option. Address each card before you stamp it. Our steps for how to write an address on a postcard keep the address and barcode areas readable, so sorting machines don’t reject a whole batch.
Do Postcard Stamps Expire?
No. U.S. postage stamps don’t expire. A postcard stamp printed with the word “Postcard” instead of a cent value is a non-denominated stamp. It stays good for the postcard rate after prices go up, so a postcard stamp you bought years ago still mails a card today with nothing added. Letter Forever stamps carry the same guarantee, as our page on whether Forever stamps expire explains.
One caveat applies to older stamps printed with a cent value. They are still valid, but they’re only worth the number printed on them. If that number is less than today’s postcard rate, you add postage to make up the difference. The USPS hub on our site has more USPS mailing guides on rates, services and mailpiece rules.
What Postage Does a Postcard to Another Country Need?
A domestic postcard stamp doesn’t cover international mail. According to USPS First-Class Mail International, one Global Forever stamp pays for a standard-size postcard, or a one-ounce letter, to any country USPS serves. The card still has to be rectangular, or an extra charge may apply. Global Forever stamps don’t expire either, so they’re worth keeping on hand if you send cards overseas often.
Frequently Asked Questions
How many postcard stamps do I put on a postcard?
One. A standard domestic postcard, rectangular and between 3.5 × 5 inches and 4.25 × 6 inches, needs a single postcard stamp in the upper-right corner of the address side. It only needs different postage if it is oversized, thicker than 0.016 inch or heavier than 3.5 ounces. In that case USPS charges it as a letter or a flat.
Are postcard stamps cheaper than regular stamps?
Yes. Postcard stamps pay the First-Class Mail postcard rate, which USPS always sets below the one-ounce letter rate that a regular Forever stamp covers. A letter Forever stamp still mails a postcard, but you pay the higher letter rate for it. USPS lists both current prices on its First-Class Mail page.
Can I put a postcard stamp on a letter?
No. A postcard stamp only covers the postcard rate, which is less than the letter rate, so it underpays a sealed envelope. USPS may return the letter to you for more postage or collect the shortfall from the recipient. Use letter Forever stamps on letters, and save postcard stamps for qualifying cards no larger than 4.25 × 6 inches.
Do postcard stamps work for postcards mailed abroad?
No. Domestic postcard stamps only cover U.S. destinations. A postcard to another country needs international postage, and USPS says a single Global Forever stamp covers a standard-size postcard up to one ounce to any country it serves. Global Forever stamps never expire, so they keep their value after international prices go up.
Sources
- USPS Domestic Mail Manual 101: Physical Standards for Letters, Cards, Flats and Parcels
- USPS: First-Class Mail (postcard and letter postage)
- USPS Newsroom: new mailing services prices effective July 12, 2026
- USPS: First-Class Mail International and Global Forever stamps
- USPS Postal Store: postcard stamps
Part of our USPS shipping guides. Related: How Much Is a Book of Stamps · Do Forever Stamps Expire · Roll of Stamps.
