Usps Medium Flat Rate Box Price 2025

Usps Medium Flat Rate Box Price 2025. Large flat rate box (12 1/4 x 12 1/4 x 6) : You can check out the starting prices for many of our domestic and international mailing and shipping options below or visit the postal explorer ® website to review the full usps ® price list.

You can check out the starting prices for many of our domestic and international mailing and shipping options below or visit the postal explorer ® website to review the full usps ® price list. Ship using free flat rate boxes and envelopes (envelopes and small boxes up to 4 lbs, medium and large boxes up to 20 lbs), starting at $30.90.