Curious about how many usps stamps you need per ounce? This guide breaks down US First‑Class postage by weight, size, and destination. Whether you're sending postcards, wedding invitations, or international mail, understanding usps stamps requirements helps you mail smarter—without surprises.
How Many Stamps Per Ounce?
For a standard 1‑oz letter, you need one Forever USPS stamp—that permanent, non-expiring postage worth the First‑Class rate. That remains true even as the price increases to 78¢ in July 2025.
How Many Stamps Per Ounce are Needed for First Class Mail?
- 1 oz letter → 1 Forever stamp (78¢)
- Each additional ounce (domestic) → +29¢ (so use 1 extra Forever or a fractional stamp)
- Postcard → 1 postcard stamp or Forever stamp (62¢ after July 13, 2025)
- 9×12 envelope (flat) → Starts at 2 Forever stamps (1.50$) and increases by weight.
Easy Rules for Calculating Postage
| Mail Type | Weight | Stamps Required (post-July 2025) |
|---|---|---|
| Standard Letter | Up to 1 oz | 1 usps stamp |
| Additional Ounce | Each extra oz | +1 usps stamp |
| Large Envelope (flat) | Up to 13 oz | Varies (typically 2–5) |
| Postcard | N/A | 1 postcard usps stamp |
| International Letter (1 oz) | Up to 1 oz | 1 Global usps stamp (~$1.70) |
Using Forever Stamps to Cover First Class Postage
Forever stamps are huge time and money savers. You can use one for any 1 oz letter, regardless of future rate hikes (78¢). For heavier mail, just add extra Forever ones or fractional stamps. Many prefer buying cheap Forever stamps in bulk rolls or sheets to always stay ahead.
Weighing Your Mail to Figure Out Postage
Accuracy matters. A kitchen or postal scale ensures you don’t underpay. Over-placing stamps is safe (you'll just overpay slightly). Need exact postage? Use USPS's online calculator.
How Many Stamps Will I Need for Larger Envelopes?
Flat (9×12) letters up to 13 oz start at $1.50, requiring two Forever stamps—then add weight stamps . For irregular pieces or square envelopes, non-machinable charges apply.
The Easiest Way to Know How Many Stamps You'll Need
- Weigh your item.
- Use the USPS rate table above.
- Affix Forever stamps for each ounce, plus extras for large size or shape.
Effortlessly Manage Your Mail with USPS Stamps Online
Buying usps stamps online or by mail is easy via the USPS store or trusted sellers like usps-store.com. Enjoy themed options—wedding usps stamps, halloween usps stamps, floral usps stamps, and personalized usps stamps. International mailers can choose global usps stamps or trackable options with QR codes.
Why People Love USPS Stamps
- Consistent value: The usps stamps 2025 price holds steady post-purchase.
- Design variety: From prepare your holiday mail with christmas usps stamps or flag usps stamps, to coolest usps stamps like art-nouveau or dragon-themed.
- Collector appeal: Limited-edition issues—like goodnight moon usps stamps or abstract expressionist usps stamps—add flair.
About USPS‑Store.com – Your Trusted Source
We offer authentic USPS stamps—including Forever, Global, and personalized varieties—with fast shipping, bulk discounts, and careful packaging. Whether you need themed stamps like wedding or christmas, or practical global usps stamps for overseas mail, our store covers it all. Stock up before rate increases, and mail with confidence.