Free tool
EDDM size checker
Every Door Direct Mail pieces must qualify as a USPS flat — and shops get burned at the counter when a piece sits exactly on the boundary. Check any size before you print.
Common sizes
Plateroom runs this check on every EDDM job automatically — plus fixes the file, adds bleed, imposes the sheet, and reminds you about the indicia before press.
Try it freeThe USPS EDDM flat rules, in plain English
To mail as EDDM Retail, your finished piece must be a flat: it has to exceed 6.125" in height or 11.5" in length — being equal isn't enough. Maximum size is 12" × 15". That's why 6.125 × 9 gets refused at the counter while 6.25 × 9 (the industry-standard EDDM postcard) sails through.
Two more counter-savers: the piece needs the EDDM indicia ("PRSRT STD / ECRWSS / EDDM Retail") printed on the mail panel, and pieces are bundled in stacks of 50–100 with a facing slip. Your local BMEU or post office takes it from there.
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More free tools: Imposition calculator