People use them for:

  • event promos

  • thank-you inserts in shipped orders

  • mini art prints

  • appointment reminders

  • quick “scan this QR code instead” handouts

  • wedding pieces

  • actual postcards

If you're mailing them through United States Postal Service, 4.25" × 6" is the largest size that still qualifies for cheaper postcard postage.

For true postcards, 16pt coated-one-side (C1S) is perfect: coated front side, and an uncoated, writable back.

For wedding suites, the more popular sizes look like this:

These usually look best on 100# uncoated cover - softer, more classic, and great for handwriting.

Small cards. Lots of jobs.