---
type: guide
title: "Postcard Mailing Size Guide to USPS Dimensions"
description: "Postcard mailing size requirements explained: exact USPS dimensions, thickness specs, and how to avoid surcharges. Print mail-ready postcards today."
resource: https://www.4over4.com/guide/postcard-mailing-dimensions-usps-requirements
tags: ["guide"]
timestamp: 2026-07-20T18:54:40.856Z
---

# Postcard Mailing Size Guide to USPS Dimensions

Postcard mailing size requirements explained: exact USPS dimensions, thickness specs, and how to avoid surcharges. Print mail-ready postcards today.

See [all guide concepts](index.md).

- Page type: guide
- URL: https://www.4over4.com/guide/postcard-mailing-dimensions-usps-requirements