EDDM Postcard Sizes and Postage Explained

The EDDM flat-size rule

EDDM is built for flat-size mail, not standard letter-size postcards. USPS defines a flat by its dimensions: the piece must be more than 6.125 inches tall, or more than 11.5 inches long, or more than 0.25 inch thick — meeting any one of those pushes it out of the letter category. At the other end, a flat can be no larger than 12 × 15 inches and no thicker than 3/4 inch. That's why a classic 4 × 6 postcard can't go through EDDM: it's letter-size, so it's mailed at regular postcard or letter rates and needs an address on every piece. EDDM pieces, by contrast, carry no names or street addresses at all. USPS delivers one to every address on the carrier routes you choose, which is what makes EDDM simple and affordable for neighborhood marketing.

Popular EDDM-eligible sizes

The EDDM indicia and address block

Because EDDM mail isn't individually addressed, every piece needs two things printed on it in the right spot. First, the postage indicia — the box in the upper-right corner that shows postage has been paid and identifies the piece as EDDM mail. Second, the address line, which uses a generic recipient like “Local Postal Customer” or “Postal Customer” instead of a name. Getting these wrong is the most common reason EDDM mailers get rejected at the post office, and a rejected bundle means a missed mail drop. When we print and mail your EDDM campaign, we place the indicia and address block for you and check them during the free pro file check. You'll see exactly where they sit on your free digital proof, and nothing is charged until you approve it.

How route pricing works

EDDM is sold by carrier route, not by mailing list. A route is one mail carrier's daily delivery path, typically covering about 400–800 homes, and USPS delivers your piece to every address on the routes you pick. Our EDDM neighborhood mailers start from $398 per route, and that price covers printing plus the mailing prep — the indicia, bundling and paperwork — so you're not piecing together printing, postage forms and drop-off logistics yourself. We don't quote postage cents here because USPS adjusts rates periodically; the route price is what matters for budgeting. To plan, start with the neighborhoods you want to reach, check how many routes they cover, and multiply. Tell us your ZIP codes and we'll map the routes and household counts with you before you commit.

Choosing the right size for your campaign

Bigger isn't automatically better, but in a stack of mail, size does buy attention. A 6.25 × 9 or 6.25 × 11 piece is plenty for a single, strong offer — one headline, one photo, one call to action. An 8.5 × 11 piece gives room for a menu, a list of services or several coupons. A 9 × 12 or larger piece makes sense for grand openings and premium services where standing out in the mailbox is the whole goal. Whatever the size, design for a two-second read: a big headline, a clear offer and your phone number or QR code. Leave the indicia and address area clear on the back, keep text inside the safe zone, and add 1/8 inch of bleed. If you're unsure, send your idea — the free file check will flag anything that won't mail.

Common EDDM sizing mistakes

A few mistakes come up again and again. Designing at 4 × 6 or 5 × 7 and then discovering the piece is letter-size and can't go EDDM — check the size rule before you design, not after. Covering the indicia area with photos or text, which forces a redesign at the last minute. Forgetting bleed, so a thin white edge shows after trimming. Putting key details too close to the edge, where they risk being trimmed or hidden by the address block. And packing in too much copy: a mail piece gets a few seconds of attention on the walk from mailbox to kitchen, so one offer and one call to action beat a wall of text every time. Every EDDM order gets a free pro file check that looks for exactly these problems, and you approve a free digital proof before anything prints or mails.

Frequently asked questions