A postcard fails EDDM when it is neither taller than 6.125 inches nor longer than 10.5 inches, or when it breaks the USPS maximums. Nearly every rejected size comes from one of seven mistakes, each listed below with the fix. For the full list of qualifying sizes and prices, see our EDDM sizes page.
Looking for the size chart? Our EDDM sizes and requirements page has every size we print drawn to scale, the USPS rule each one clears and today's price. This post is the troubleshooting companion: why a size fails, and what to change.
The Rule Your Postcard Has to Pass
USPS treats an EDDM Retail piece as a flat. It "must weigh no more than 3.3 ounces and must have a length greater than 10-1/2 inches long, or a height greater than 6-1/8 inches high, or a thickness greater than 1/4 inch thick" (USPS DMM 143, section 2.5.1). It also cannot be more than 15 inches long, 12 inches high or 3/4 inch thick (USPS DMM 101). Every mistake below breaks one of those two sentences.
Mistake 1: Mailing a 6 by 9 Postcard
This is the most common one, because a 6 by 9 looks exactly like an EDDM postcard. At 6 inches tall it falls 0.125 inch short of the height rule, and at 9 inches long it is well under 10.5. It fails both ways.
The fix: move to a 6.25 x 9 or a 6.5 x 9 postcard. The extra quarter or half inch of height is what makes the piece a flat.
Mistake 2: Using a 4 by 6, 5 by 7 or Small Square Card
A 4 by 6 or 5 by 7 card is a letter-size piece to USPS. It is not tall enough, long enough or thick enough on any count, so it cannot go at the EDDM Retail rate. A 6 by 6 square fails for the same reason: 6 inches is under both thresholds.
The fix: if you like a compact card, the 6.5 x 8 is the smallest postcard we print, and it qualifies on height.
Mistake 3: Reading "And" Where USPS Wrote "Or"
Some people rule out narrow pieces because they think a flat has to be taller than 6.125 inches and longer than 10.5. It does not. Clearing one dimension is enough, which is why a 4.25 x 11 flyer and a 4.5 x 12 postcard qualify on length alone, even though both are well under 6.125 inches tall.
The fix: check each dimension separately. If the short side is 6.125 inches or less, the long side must be over 10.5 inches.
Mistake 4: Sending an 11 x 17 Flat
An 11 x 17 sheet is 17 inches long, over the 15-inch maximum, so it cannot mail flat. It has to be folded to 8.5 x 11, which clears both rules.
The fix: design for the folded panels, not one big poster. When you order the 11 x 17 flyer the fold is preselected. If you want one large flat piece with no fold, the 9 x 12 and 8.5 x 14 are the largest sizes we mail flat.
Mistake 5: Measuring the File Instead of the Trimmed Piece
USPS measures the piece as it arrives in the mailbox, after trimming. Print files are bigger than that, because backgrounds extend 0.125 inch past the trim on every edge (the bleed). A designer who builds a 6 by 9 card and adds bleed ends up with a 6.25 by 9.25 document, which looks like a qualifying size on screen but trims back down to 6 by 9.
The fix: start from the finished size and add the bleed on top. A 6.5 x 9 postcard needs a 6.75 by 9.25 document. Our free EDDM templates are already set up this way, and the EDDM file checker flags size and bleed problems before you upload.
Mistake 6: Ignoring Weight and Thickness
A single printed card or flyer is nowhere near 3.3 oz or 3/4 inch. The limits start to matter when a piece grows: extra pages, inserts, very heavy stock or something attached. Over 3.3 oz, the piece no longer qualifies for EDDM Retail, whatever its size.
The fix: weigh a finished sample of anything more than a single sheet before you print the whole run.
Mistake 7: No Room Left for the Postage Box
The size can be right and the piece can still be held up if the mailing side has no clear space for the postage box (the indicia) and the "Postal Customer" line. Both go in the top-right area of the address side, which your artwork has to leave empty.
The fix: keep that corner clear. With Full Service we place a permit postage box; with Print Only we place the EDDM Retail postage box. Either way, the templates mark the space for you.
Frequently Asked Questions
Why doesn't my 6 by 9 postcard qualify for EDDM?
It is 6 inches tall, 0.125 inch under the 6.125-inch height rule, and 9 inches long, under the 10.5-inch length rule. Move to a 6.25 x 9 or 6.5 x 9.
Can I use a 5 by 7 postcard for EDDM?
No. A 5 by 7 is a letter-size card to USPS. The smallest postcard we print that qualifies is the 6.5 x 8, which clears the height rule.
Does a folded piece count at its folded size?
Yes, USPS measures the piece as mailed. That is why an 11 x 17 flyer, which is too long to mail flat, qualifies once it is folded to 8.5 x 11.
Where can I see every size that qualifies?
On our EDDM sizes page: every size we print, drawn to scale, with the rule it clears and its current price.
Not sure about a size? Type it into the EDDM size checker to see it drawn against the USPS rule. Once it passes, see the homes on your routes and the price, free. Questions? Call (346) 306-EDDM (3336).
