For a standard 1-ounce certified letter paid entirely with Forever stamps, you need eight stamps. That covers the $0.78 First-Class letter rate plus the $5.30 Certified Mail fee, a total of $6.08.1United States Postal Service. Notice 123 Price List Eight Forever stamps come to $6.24, so you overpay by $0.16, but USPS accepts the letter without refunding the difference. If you add a return receipt or restricted delivery, the count goes up from there.
Stamp Counts at a Glance
All counts below assume a standard 1-ounce First-Class letter and $0.78 Forever stamps, rounded up to the next whole stamp:
- Certified Mail only: $6.08 → 8 stamps
- Certified Mail with electronic return receipt: $8.90 → 12 stamps
- Certified Mail with physical return receipt (green card): $10.48 → 14 stamps
- Certified Mail with restricted delivery: $14.48 → 19 stamps
- Certified Mail with restricted delivery and physical return receipt: $18.88 → 25 stamps
Why the Math Works This Way
Certified postage has two parts. The first is ordinary First-Class postage based on size and weight. The second is a flat $5.30 fee for the Certified Mail service itself, which gives you a tracking number, delivery confirmation, and an official mailing receipt.1United States Postal Service. Notice 123 Price List Both amounts must be prepaid, and both can be paid with stamps affixed directly to the envelope.2United States Postal Service. 604 Postage Payment Methods and Refunds
A single Forever stamp covers one ounce of First-Class Mail at $0.78. Add the $5.30 certified fee and you’re at $6.08. Since stamps can’t be split, divide by $0.78 and round up to eight. The total postage affixed must equal or exceed the mail class charge plus all extra service fees.2United States Postal Service. 604 Postage Payment Methods and Refunds
Return Receipt Add-Ons
A return receipt gives you a record of who signed for the delivery, and it comes in two forms.
The physical green card (PS Form 3811) costs $4.40 extra and comes back to you in the mail with the recipient’s actual signature. For a 1-ounce letter, that brings the total to $10.48, or 14 Forever stamps ($10.92).1United States Postal Service. Notice 123 Price List
The electronic return receipt costs $2.82 extra and delivers the same information to your email or USPS tracking page. Total postage becomes $8.90, or 12 Forever stamps ($9.36).1United States Postal Service. Notice 123 Price List For legal purposes, both generally carry the same weight.
Restricted Delivery
Restricted delivery ensures the letter reaches only the addressee or someone they’ve authorized to receive it.3United States Postal Service. What is Restricted Delivery The combined fee for Certified Mail with restricted delivery is $13.70, replacing the standard $5.30 certified fee.1United States Postal Service. Notice 123 Price List For a 1-ounce letter, that’s $0.78 plus $13.70, which comes to $14.48. That takes 19 Forever stamps.
Heavier Letters and Large Envelopes
Weight changes the base postage, and so does size. First-Class letters top out at 3.5 ounces, and large envelopes (flats) go up to 13 ounces.4United States Postal Service. First-Class Mail
Each additional ounce on a First-Class letter raises the base postage. Weigh the envelope, look up the current rate, add $5.30 for the certified fee, and round up to the next whole stamp.
Legal-size or manila envelopes that exceed standard letter dimensions become flats and cost more from the start. A 1-ounce flat is $1.63 in First-Class postage, rising to $5.04 at 13 ounces.5United States Postal Service. Notice 123 – January 2026 Price Change With the $5.30 certified fee added, a 1-ounce flat runs $6.93, or 9 Forever stamps ($7.02). Heavier flats add up quickly in stamp form.
When to Skip Stamps
Once you’re stacking a dozen or more stamps on an envelope, you’re overpaying and running out of room. Paying at the post office counter or printing postage online lets you pay the exact amount, down to the cent. The clerk weighs your envelope, calculates the total, and prints a label. That saves the small overage on the certified letter itself and matters more as add-ons pile up.1United States Postal Service. Notice 123 Price List
Mailing It the Right Way
Fill out the Certified Mail receipt (PS Form 3800) with the recipient’s name and address. The form has a barcode and tracking number pre-printed on it. Peel off the adhesive backing and attach it to the front of the envelope. If you’re using a physical return receipt, fill out PS Form 3811 with both addresses and attach it to the back.
Affix your stamps, then take the piece to a USPS counter. The clerk postmarks the receipt portion of Form 3800, and that postmarked receipt is your legal proof of mailing with the date stamped on it.6U.S. Postal Service. PS Form 3800 – Certified Mail Receipt You can technically drop a stamped certified letter in a collection box, but then your receipt won’t get postmarked, which defeats the point.
One Thing Certified Mail Doesn’t Cover
Certified Mail proves delivery. It doesn’t insure the contents. If your item is lost or damaged, the certified fee gets you nothing toward its value; you’d need to buy USPS insurance separately.7United States Postal Service. 500 Additional Mailing Services For most certified letters, the paper inside is a copy and the real value is the postmarked receipt, so this rarely matters. Worth knowing before you send an original document.