Can You Use Forever Stamps on Postcards? What to Know Before Mailing
Yes, a U.S. Forever stamp can be used to mail a postcard within the United States. Because a Forever stamp covers the current postage for a standard one-ounce First-Class Mail letter, its value is generally higher than the postcard rate. The postcard will be delivered, but the extra postage is not refunded. Size, shape, thickness, and destination still matter, so it helps to check the current U.S. Postal Service (USPS) rules before mailing.
Can You Use a Forever Stamp on a Postcard?
For a standard domestic postcard, one Forever stamp is normally sufficient. Forever stamps do not become invalid when USPS raises postage prices. A stamp bought years ago can still be used at its current face value for eligible domestic First-Class Mail postage.
The important detail is that a Forever stamp is intended to cover the postage for a one-ounce letter—not specifically the postcard rate. Since the postcard rate is usually lower, applying one Forever stamp to a regular postcard typically pays more than required. USPS does not return the difference or issue change.
This makes a Forever stamp a convenient option when someone already has stamps at home, but it may not be the least expensive choice. A postcard-rate stamp, or a combination of lower-denomination stamps that equals the current postcard price, can avoid paying more than necessary.
How Forever Stamps and Postcard Postage Work
USPS sets separate prices for postcards and letters. A mailpiece qualifies for the postcard price only when it meets USPS postcard size and format requirements. A card that is too large, too small, unusually shaped, or too thick may instead be charged at the letter rate or another applicable rate.
A Forever stamp’s postage value changes when the domestic First-Class Mail letter price changes. The stamp itself does not need to be exchanged or updated. If the amount printed on a stamp is not shown, it still counts toward the current eligible postage amount under the Forever-stamp terms.
Postcard postage is also subject to rate changes. For the current price, check the USPS Postal Explorer or postage price information before mailing, especially when using older postcard stamps or sending a large batch. The price on a postcard stamp does not automatically increase just because the stamp remains unused.
When One Forever Stamp May Not Be Enough
One Forever stamp is a simple choice for an ordinary domestic postcard, but it is not a universal stamp for every postcard-shaped item. Extra postage may be due if the piece does not qualify for the postcard rate, weighs more than the amount covered, or is being sent outside the United States.
Oversized or Nonstandard Cards
A large card may be charged as a letter even if it looks like a postcard. USPS generally defines a postcard-price mailpiece as rectangular, at least 3.5 inches high and 5 inches long, and no more than 4.25 inches high and 6 inches long. It must also meet thickness and other machinability standards. Measurements and rules can change, so consult USPS before mailing an unusual card.
For example, a photo card measuring 5 by 7 inches is larger than the standard postcard maximum. It may qualify for letter postage instead, provided it meets letter dimensions and other requirements. In that case, one Forever stamp may cover the base postage for a domestic letter weighing up to one ounce, but additional postage may apply if the card is heavier or nonmachinable.
Heavy or Thick Cards
A postcard with attached objects, layered decorations, or unusually heavy stock may exceed the allowed thickness or weight. A card can also be too rigid or uneven to travel through automated processing equipment. These features may trigger a surcharge or require a different mailing price.
When a card is unusually heavy or decorated, weighing it at a USPS counter is safer than guessing. A Forever stamp covers a specific postage value; it does not guarantee that every item bearing the stamp qualifies for standard letter or postcard service.
International Postcards
A regular domestic Forever stamp is not the right postage for a postcard mailed to another country. International mail uses international postage rates. A Global Forever stamp is designed for eligible international First-Class Mail and can be used for a one-ounce letter or postcard to an international destination, subject to USPS service rules.
International prices and destination requirements can differ from domestic rates. Confirm the current amount with USPS, and make sure the destination accepts the mailpiece as addressed. A domestic Forever stamp on its own may leave international postage short, causing delay or return.
Postcard Size and Mailing Requirements
To receive the postcard price, a mailpiece generally needs to meet USPS size and shape standards. A card that misses a limit may be treated as a letter instead. The following dimensions are useful reference points for standard postcard pricing; USPS rules should be checked for the latest requirements.
| Feature | General USPS postcard standard | Why it matters |
|---|---|---|
| Shape | Rectangular | Nonrectangular pieces may be charged at a higher rate. |
| Minimum size | 3.5 inches high by 5 inches long | Smaller pieces may not qualify for mail processing. |
| Maximum size | 4.25 inches high by 6 inches long | Larger cards generally fall under letter pricing or other rules. |
| Thickness | Generally at least 0.007 inch and no more than 0.016 inch for postcard pricing | Too-thin or too-thick pieces may not qualify. |
Dimensions are not the only consideration. A card’s flexibility, surface, and thickness can affect whether it can be processed as a postcard. Square cards, for instance, do not meet the usual rectangular format and may require additional postage. A decorative card with a raised attachment may also be treated differently from a flat card.
For cards sold as postcards, the packaging or product description can be helpful, but it is not a guarantee that the finished mailpiece meets USPS standards. Added stickers, ribbons, or embellishments can change the card’s thickness and shape. If postage accuracy matters, have the completed card checked at a post office.
How to Calculate the Right Postage
Choosing postage is straightforward when the card is a standard domestic postcard. First, confirm the destination is within the United States and measure the card. Then check the current USPS postcard rate and compare it with the value covered by the stamps available.
- Measure the card. Check its length, height, and thickness, and confirm it is rectangular.
- Check the destination. Domestic and international mail have different postage rules.
- Look up the current rate. Use USPS price information rather than relying on an old rate printed in an article or guide.
- Apply enough postage. One domestic Forever stamp is typically more than enough for a standard domestic postcard, while an international card needs international postage.
- Ask USPS if the card is unusual. A clerk can weigh and assess oversized, thick, rigid, or heavily decorated mailpieces.
Postage can also be paid at a post office or through an eligible USPS postage service. This can be useful for a large mailing, a card with uncertain dimensions, or a piece that needs tracking or a different service. Postcards sent with standard postcard postage generally do not include tracking.
Common Questions About Forever Stamps on Postcards
Can an old Forever stamp still be used?
Yes. A genuine Forever stamp remains valid for eligible domestic postage even after USPS changes rates. It counts toward the current postage value associated with that stamp. It does not, however, automatically cover every mailing service, international postage, or extra charges for an oversized or nonstandard card.
Will USPS refund the extra postage?
No. If one Forever stamp pays more than the postcard rate, USPS does not refund the difference. The card is still eligible for delivery if it meets the relevant mailing rules and has sufficient postage.
Can two Forever stamps be used on one postcard?
Yes, stamps can generally be combined to pay postage. But two Forever stamps will usually be far more postage than a standard domestic postcard needs. The excess is not returned, so using a single stamp or the exact postcard-rate amount is usually more economical.
Can a Forever stamp be used on a greeting card?
Often, yes, if the greeting card fits the domestic letter requirements and weighs no more than one ounce. A large, square, rigid, or unusually thick greeting card may need extra postage. The envelope’s dimensions and finished weight—not the fact that it contains a greeting card—determine the applicable rate.
Does a Forever stamp include delivery confirmation?
No. Standard postage does not automatically provide tracking or delivery confirmation for a postcard. If proof of mailing or tracking is important, ask USPS about available services. Some services may require a different format or postage than ordinary postcard mailing.
Practical Tips for Mailing Postcards
- Use a postcard-rate stamp when saving postage matters. A Forever stamp is convenient, but the postcard rate is usually lower.
- Do not assume every card is a postcard. A large, square, thick, or oddly shaped card may be priced as a letter or require an additional charge.
- Check current rates before mailing. Postage prices can change, and older printed information may be out of date.
- Keep the address and postage area clear. Stickers and writing should not obscure the delivery address, return address, or postage area.
- Use international postage for foreign destinations. A domestic Forever stamp alone is not sufficient for international mail.
- Ask at the counter when uncertain. A quick measurement or weight check can prevent postage due or a returned item.
USPS postage and mailpiece standards are described in the Domestic Mail Manual and the USPS letters and postcards guidance. These official resources are the best place to confirm current rates, size limits, and service options before mailing a card.