What a 1 Forever Stamp Covers Today
A Forever stamp sold in the United States costs the same as a First-Class Mail one-ounce letter rate and covers sending a 1 oz letter through the U.S. Postal Service First-Class Mail service. As of 2026, this rate is typically $0.66. The primary use is for a single ounce envelope mailed domestically via USPS First-Class Mail; additional ounces, larger sizes, or special services require extra postage. This overview explains current coverage, weight and size limits, when to add more stamps, and how to confirm exact prices.
Current First-Class Mail Pricing (2026)
The price of a 1 Forever stamp matches the First-Class Mail one-ounce letter rate. Rates are set by the Postal Regulatory Commission and can change annually; the most recent adjustment occurred in January 2026. For the most up-to-date pricing, check the USPS official rate chart or retail listings at post offices and online stores. The stamp is designed to always cover the one-ounce First-Class price, even as rates increase.
Price Table: 1 Forever Stamp and Common First-Class Rates
| Item | Price | Source/Context |
|---|---|---|
| 1 Forever stamp (1 oz letter) | $0.66 (typical 2026) | USPS First-Class Mail one-ounce letter rate |
| Additional ounce (each) | $0.28 (typical 2026) | First-Class Mail additional ounce rate |
| Postcard (non-bill/notice) | $0.66 (typical 2026) | USPS Postcard rate |
| Letters over 1 oz | Base $0.66 + $0.28 per extra oz | Retail plus per-ounce charges |
Weight and Size Limits for a Single 1 Forever Stamp
The 1 Forever stamp covers letters up to 1 ounce within standard size limits. First-Class Mail letter requirements specify that paper letters must weigh no more than 3.5 ounces to qualify for the letter rate; anything heavier moves into parcels. The maximum size for letter-rate pieces is 11.5 inches long by 6.125 inches high, with a combined length and girth not exceeding 24 inches. If your mail exceeds any of these thresholds, you will need additional postage beyond the single stamp.
Quick Coverage Checklist
- Weight: Up to 1 oz (use a 1 Forever stamp); 1–3.5 oz requires more postage.
- Size: Must fit within 11.5" L × 6.125" H; total L+girth ≤ 24".
- Type: Standard domestic envelope through USPS First-Class Mail.
- Destination: Only domestic U.S. delivery; international requires different service.
When a 1 Forever Stamp Is Not Enough
You need additional postage when the letter exceeds 1 ounce, is oversized, or is sent to a non-standard destination. For each additional ounce beyond the first, add approximately $0.28 in most years, but exact pricing depends on the current rate schedule. Larger envelopes, square cards, or rigid materials may also require extra fees or a different service level such as USPS Retail Ground or Priority Mail. Always verify the latest pricing at the post office or on the USPS website before mailing.
Examples Requiring More Than One Stamp
- 1.5 oz letter: 1 Forever stamp + 1 additional ounce charge (~$0.28).
- Oversized letter: May require Retail Ground or Priority Mail pricing instead of Forever stamps.
- Nonmachinable items: Square envelopes or thick materials may incur extra nonmachinable fees.
International and Special Services
A 1 Forever stamp does not cover international mail, which requires specific international postage rates and often additional customs forms. It also does not cover tracking, insurance, or priority services. For items needing proof of delivery, expedited delivery, or protection against loss or damage, choose the appropriate specialty product such as Priority Mail, Registered Mail, or Certified Mail. These services have separate pricing and should not be substituted with Forever stamps alone.
How to Confirm the Exact Cost Before Mailing
Prices can vary slightly by location and purchase type, so it is best to confirm current rates before preparing mail. Use the USPS official Rate Calculator, visit a post office, or check authorized retail sellers. Weigh your letter with a postal scale if you are near the 1 oz boundary, and measure length and girth with a ruler to ensure it fits the letter guidelines. Accurate measurement and up-to-date pricing prevent returned mail or unexpected charges at the counter.