How many stamps does a postcard need? A standard-size postcard needs exactly one First-Class Mail postcard stamp — for example, a 4×6-inch vacation card gets a single postcard-rate stamp in the top-right corner and nothing else. The postcard rate is lower than the letter rate, so a dedicated postcard stamp is the right postage; a Forever stamp will also carry it, but you overpay the difference.
Key Takeaways
- One postcard = one postcard stamp. A single First-Class Mail postcard stamp covers a standard card end to end within the United States.
- The postcard rate is its own, lower price. USPS sets the postcard rate a few cents below the first-class one-ounce letter rate, which is exactly why a dedicated postcard stamp exists — check current USPS pricing for today’s figure.
- Size decides the rate. A card qualifies for the postcard price only between 3½×5 inches and 4¼×6 inches; anything larger or thicker is charged — and stamped — as a letter.
- Postcard Forever stamps don’t expire. A non-denominated postcard stamp stays valid at the postcard rate even after prices rise.
- Buy them anywhere stamps are sold. The Post Office, the USPS Postal Store, kiosks, and many grocery and drug stores carry postcard postage, and bulk coils of 100 exist for high-volume senders.
How Many Stamps Does a Postcard Need?
One. A standard postcard mailed anywhere in the United States needs a single First-Class Mail postcard stamp. You do not add a letter stamp on top of it, and you do not need two postcard stamps — the one postcard-rate stamp is the full postage for the card. Place it in the upper-right corner on the address side, the same corner you would use for a letter.
The one-stamp rule holds only while the card actually qualifies as a postcard in the USPS Domestic Mail Manual. To take the postcard price, a card must be rectangular, at least 3½ inches high by 5 inches long, no larger than 4¼ inches by 6 inches, and between 0.007 and 0.016 inch thick. Go past any of those limits — an oversized art card, a thick card stock, a card in an envelope — and USPS reclassifies the piece as a letter. A letter needs a letter stamp, and if it is also heavy or oversized it can need more, which is a separate calculation covered on our guide to how many stamps a large envelope needs.
How Much Is a Postcard Stamp?
A postcard stamp costs 65¢ — the current First-Class Mail postcard rate, which rose from 61¢ on July 12, 2026, while the one-ounce letter rate moved to 82¢ (see current USPS pricing before you buy, since rates change). The point worth remembering is not the exact number but the gap: the postcard rate is always set below the letter rate. That is the whole reason a separate postcard stamp exists — it prices the smaller, lighter mailpiece correctly instead of charging it as a letter.
Because the two rates differ, using the right stamp matters at volume. Mail one card and the difference is trivial; mail a few hundred holiday cards or a marketing run and the postcard stamp versus a letter stamp on each piece adds up. If you are buying stamps in general and want the per-stamp math on a full book, our book of stamps cost breakdown covers letter postage the same way this page covers postcard postage.
| Mailpiece | Stamp needed | Qualifying size | Rate class |
|---|---|---|---|
| Standard postcard | 1 postcard stamp | 3½×5 in to 4¼×6 in | Postcard (lowest) |
| Oversized / thick card | 1 letter stamp | Over 4¼×6 in or over 0.016 in thick | First-Class letter |
| One-ounce letter | 1 Forever stamp | Up to 6⅛×11½ in, in an envelope | First-Class letter |
| Postcard to another country | Global postcard postage | Postcard size, international | International (higher) |
Can I Use a Regular Forever Stamp on a Postcard?
Yes. A standard letter Forever stamp is always worth at least the current letter rate, so it more than covers a postcard — USPS will deliver the card without extra postage due. The only cost is to you: a letter Forever stamp is priced at the letter rate, so putting one on a postcard means you pay the letter rate for a piece that only owed the lower postcard rate. On a single card, nobody minds. Across a stack of cards, you are leaving money on the counter.
The reverse does not work: a postcard stamp is worth only the postcard rate, so it cannot fully pay for a letter. If you stick a postcard stamp on a sealed envelope, USPS treats the letter as underpaid and may return it for more postage or bill the recipient. Match the stamp to the mailpiece — postcard stamp on postcards, letter stamp on letters.
Where Can I Buy Postcard Stamps?
Postcard postage is sold anywhere general postage is sold, plus a few places specific to it:
- The Post Office counter — ask specifically for “postcard stamps,” because the default stamp a clerk reaches for is a letter Forever stamp.
- The USPS Postal Store online — postcard stamps ship to your door in singles, panes, and coils.
- Self-service kiosks and stamp machines inside many Post Office lobbies, available after hours.
- Grocery stores, pharmacies, big-box, and office-supply retailers — many carry postage near the customer-service desk, though selection of the postcard denomination specifically is hit or miss, so call ahead.
If you are unsure where postage is stocked near you in general, our overview of where to buy stamps maps every outlet; this page’s only added tip is to name the postcard denomination out loud so you don’t leave with letter Forever stamps by default.
How Do I Buy Postcard Stamps in Bulk?
If you send postcards in quantity — a save-the-date run, a small-business mailer, a classroom project — buy the postcard denomination in a coil or pane instead of by the single. The USPS Postal Store sells postcard stamps in a coil of 100 (a wound roll) and in panes, so you peel from a strip rather than fumbling with loose stamps. The mechanics are the same as a letter-stamp coil, which we walk through on our roll of stamps guide; the only difference is the denomination printed on the stamp.
For a genuinely large commercial mailing, presorted business rates run well below the retail postcard price, but they require a permit and minimum piece counts and are a different process from buying stamps. For most senders, a coil of 100 postcard stamps is the practical “bulk” answer. Address each card correctly before you stamp it — our notes on how to write an address on a postcard and on USPS postcard clear zones keep the barcode area readable so a full batch doesn’t get kicked out by the sorting machines.
Do Postcard Stamps Expire?
No. A postcard stamp sold as a non-denominated “Postcard” Forever stamp never expires and never loses value. It is always worth the current postcard rate, so a postcard stamp bought years ago still mails a postcard today with nothing extra to add — the same guarantee that applies to letter Forever stamps, explained on our page about whether Forever stamps expire.
One caveat: older stamps that show a printed cents value (a denominated stamp, not a Forever stamp) are still valid, but they are only worth the number printed on them. If that number is below today’s postcard rate, you make up the difference with additional postage. When in doubt, a current postcard Forever stamp is the clean choice. For the wider USPS mailing picture — rates, services, and mailpiece rules — start at our USPS shipping hub.
Frequently Asked Questions
How many stamps do I put on a postcard?
One First-Class Mail postcard stamp, placed in the upper-right corner of the address side. A standard-size domestic postcard never needs a second stamp. It only needs different postage if it is oversized or thick enough that USPS reclassifies it as a letter.
Is a postcard stamp cheaper than a regular stamp?
Yes. The First-Class Mail postcard rate is set below the one-ounce letter rate, which is why a dedicated postcard stamp exists. A letter Forever stamp will carry a postcard, but you pay the higher letter rate for it, so the postcard stamp is the cheaper, correct choice for cards.
What makes a card too big for the postcard rate?
A card larger than 4¼ by 6 inches, or thicker than 0.016 inch, no longer qualifies for the postcard price and is charged as a First-Class letter. It then needs a letter stamp instead of a postcard stamp. Cards below 3½ by 5 inches are non-mailable and are not accepted at all.
Can I put a postcard stamp on a letter?
No. A postcard stamp is worth only the postcard rate, which is less than the letter rate, so it underpays a sealed envelope. USPS may return the letter for more postage or collect the shortfall from the recipient. Use a letter Forever stamp on letters and save postcard stamps for postcards.
Do I need extra postage to mail a postcard to another country?
Yes. A domestic postcard stamp does not cover international mail. A postcard headed outside the United States needs international postage — a Global Forever stamp or the equivalent — which is priced higher than the domestic postcard rate. Ask at the Post Office counter or check current USPS international prices before mailing.
Where can I buy postcard stamps in bulk?
The USPS Postal Store sells postcard stamps online in coils of 100 and in panes, and the Post Office counter can supply them in quantity. For very large commercial mailings, presorted business postcard rates are lower still but require a mailing permit and minimum piece counts.
Sources
- USPS Newsroom — New mailing services prices effective July 12, 2026 (postcard and letter rates)
- USPS — Postage Prices (current rates)
- USPS Domestic Mail Manual 101 — Physical Standards for Letters and Cards
- USPS FAQ — 2026 Postage Price Change
- USPS — First-Class Mail (postcards)
Part of our USPS shipping guides. Related: Where to Buy Stamps · Book of Stamps Cost · Roll of Stamps.
