How thick can my printed piece be and still mail as a letter?

To qualify for USPS letter postage, your printed piece has to stay inside specific thickness and weight limits. Most standard card and paper stocks fall comfortably within them.

• Common stocks like 14pt and 16pt sit well under the thickness cap.
• Go past 0.25 inches or 3.5 ounces and the piece bumps into flat or parcel rates, which cost more.
• Match your stock weight to the postal category before ordering so postage does not surprise you at the counter.