Do I need to leave space on my postcard design for the mailing address?

Yes. USPS needs a clear address area on the right half of the back of the card, plus a clean strip along the bottom for the barcode. Skip these zones and you risk delivery delays or returned mail.

• Address block: keep the right half of the back open for the recipient's address.
• Barcode zone: leave the bottom strip clear so the postal barcode can be read.
• Keep it clean: avoid busy backgrounds or dark colors behind the address that make it hard to scan.