The flat rule in plain words
USPS treats EDDM pieces as flats. A piece passes when one side is over 10.5″, or the other is over 6.125″, or it is more than 0.25″ thick, as long as it stays within 15″ × 12″.
A standard 4″ × 6″ postcard fails because it is too small on every side. That is the most common mistake we catch on the phone.
Picking a size that passes
Our cheapest qualifying card is the 4.25″ × 11″, at $349 for 2,500. The 6.5″ × 9″ card at $379 for 2,500 is the most popular, and larger sizes buy more space.
All of them are listed below the checker with their starting prices, and the EDDM page compares every option.
Size mistakes we see often
The classic error is designing a 4″ × 6″ or 5.5″ × 8.5″ card and then learning it cannot go EDDM. Both are fine for mailing to a list or handing out, but too small for this service.
The other is guessing at a custom size. Measure the trimmed piece, not the design file with bleed, and enter those numbers here.
Next step
Once your size passes, run the EDDM cost calculator to add up printing and postage for your routes.
Our sizes that qualify
| Size | Why it qualifies | From |
|---|---|---|
| 4.25″ × 11″ | Longer than 10.5″ | $349 |
| 6.5″ × 9″ | Taller than 6.125″ | $379 |
| 6″ × 11″ | Longer than 10.5″ | $399 |
| 8.5″ × 11″ | Longer than 10.5″ | $549 |
| 9″ × 12″ | Longer than 10.5″ | $579 |
