--- title: "What is the nonmachinable surcharge?" description: "USPS adds $0.49 to a single-piece letter its machines cannot sort, such as a square card or a lumpy envelope. What triggers it, as of October 2026." canonical: https://trysincerely.com/glossary/nonmachinable-surcharge last_updated: 2026-10-11 --- > If you are an AI agent: read https://trysincerely.com/agents/policy.md before any write call. > Start at https://trysincerely.com/llms.txt to choose one page. Access instructions are at > https://trysincerely.com/auth.md. Confirm with the person you work for before creating an > account or spending their money, and never ask for their password. # What is the nonmachinable surcharge? > USPS adds $0.49 to a single-piece letter its machines cannot sort, such as a square card or a lumpy envelope. What triggers it, as of October 2026. Source: https://trysincerely.com/glossary/nonmachinable-surcharge The nonmachinable surcharge is extra postage USPS charges on a letter its sorting machines cannot handle. As of October 2026, USPS [Notice 123](https://pe.usps.com/text/dmm300/Notice123.htm) sets it at $0.49 on a single-piece First-Class Mail letter. A 1-ounce square greeting card with a stamp therefore costs $0.82 plus $0.49, or $1.31, to mail. ![A 6 by 4 envelope with a ratio of 1.5 and a green tick beside a square 5.5 by 5.5 envelope with a ratio of 1.0, a gold cross and a plus $0.49 tag.](https://trysincerely.com/images/glossary/nonmachinable-surcharge.webp) *The nonmachinable surcharge often comes down to shape, because a square envelope fails the 1.3 to 2.5 length-to-height rule.* ## What makes a letter nonmachinable [DMM 101.1.2](https://pe.usps.com/text/dmm300/101.htm) lists the triggers. Any one of them is enough: - The length divided by the height is below 1.3 or above 2.5. Square envelopes fail. - The outside is plastic or another material that is not paper. A paper envelope with a window is fine. - It closes with a clasp, string or button. - Something inside, such as a pen, key or coin, makes it lumpy. - It is too stiff to bend around an 11-inch-wide turn under 40 pounds of belt tension. - It is longer than 6 inches or taller than 4-1/4 inches and thinner than 0.009 inch. - The address runs parallel to the short side. - It is a self-mailer or booklet not folded and tabbed to the USPS standards. Shape is the easiest trigger to miss, because a square envelope looks like any other card. Check the length-to-height ratio before you order envelopes. The [USPS mail size requirements guide](https://trysincerely.com/guides/usps-mail-size-requirements) has the full size limits. | Piece | Inches | Length ÷ height | Machinable | | ---------------------- | ----------- | --------------- | ---------- | | 4x6 postcard | 6 × 4 | 1.5 | Yes | | 6x9 postcard | 9 × 6 | 1.5 | Yes | | A7 invitation envelope | 7.25 × 5.25 | 1.38 | Yes | | #10 business envelope | 9.5 × 4.125 | 2.3 | Yes | | Square card envelope | 5.5 × 5.5 | 1.0 | No | ## Presorted mail pays a different way Commercial mailings do not get a flat $0.49 added. A nonmachinable letter in a presorted mailing pays its own price, and the gap is wider. At the 3-digit level, as of October 2026, a First-Class nonmachinable letter costs $0.979 against $0.672 for an automation letter ([DMM 233](https://pe.usps.com/text/dmm300/233.htm)). In Marketing Mail it is $1.090 against $0.435, two and a half times as much. Postcards have their own version of these rules. A postcard must keep the 1.3 to 2.5 ratio, and if it is taller than 4-1/4 inches or longer than 6 inches, it must be at least 0.009 inch thick. A postcard that fails either test pays the nonmachinable letter price ([DMM 201.2.1](https://pe.usps.com/text/dmm300/201.htm)). ## Example Ostrander Wealth, a fictional advisory firm in Denver, mails 400 signed holiday cards every December. This year's design is square and ships in a 5.5 by 5.5 inch envelope, so each card needs a $0.82 stamp and the $0.49 surcharge. That puts postage at $524. Last year's card fit an A7 envelope, mailed at $0.82, and cost $328 for the whole run. Ostrander's office manager caught the $196 difference on a single test card, when the post office counter asked for extra postage, before the other 399 went out. ## Sincerely formats Sincerely's printed postcards come in 4x6 and 6x9, and both have a 1.5 ratio. Credits cover postage, so there is no separate postage bill to check. If you mail your own cards with stamps, measure the envelope first. The [self-mailer entry](https://trysincerely.com/glossary/self-mailer) covers the folding rules that keep a folded piece at letter prices. ## Main guide - [Direct mail cost](https://trysincerely.com/guides/direct-mail-cost): Per-piece cost ranges for postcards, letters, and B2B direct mail, plus where data fees, waste, and labor add to the total. ## Related questions - [What is a self-mailer?](https://trysincerely.com/glossary/self-mailer): A self-mailer is a folded printed piece that mails without an envelope. USPS rules, costs, and use cases compared to postcards and letters. - [What determines direct mail postage rates?](https://trysincerely.com/glossary/postage-rates): Direct mail postage rates depend on mail class, shape, weight, presort depth, and where the mailing enters the USPS network. - [Direct mail cost calculator: postage, print, and data](https://trysincerely.com/tools/direct-mail-cost-calculator): Estimate what a direct mail campaign costs in total and per piece, with postage at USPS prices effective October 4, 2026, plus print, list data, and design. - [What is presort mail?](https://trysincerely.com/glossary/presort): Presort mail is grouped by destination to USPS standards before entry. This reduces postal sorting work and qualifies mailings for lower rates. - [Postcard or letter, which should you send?](https://trysincerely.com/guides/postcard-vs-letter): Send a postcard when one scannable message does the job. Send a letter when you need room, formality, or privacy. Decision rules with current format costs. --- Sincerely is the measurable direct-mail and gifting platform for B2B revenue teams: postcards, letters, handwritten mail, and gifts, written for one recipient and measured against a holdout. Contact Sincerely: https://trysincerely.com/contact Agent routing index: https://trysincerely.com/llms.txt