USPS Priority Mail Express

USPS Priority Mail Express is the Postal Service's fastest domestic option, guaranteeing 1- to 3-day delivery by 6 p.m. for packages up to 70 lbs. Through Shippo, commercial rates start at $31.11 for a Flat Rate Envelope, with tracking and up to $100 of insurance included (rates pulled July 22, 2026).

Updated July 22, 2026. Rates pulled July 22, 2026.

In this article

• What is USPS Priority Mail Express?
• How much does USPS Priority Mail Express cost?
• What's included: guarantee, insurance and tracking
• Flat rate vs. weight-based pricing
• USPS Priority Mail Express vs. Priority Mail: which should you use?
• Frequently asked questions

What is USPS Priority Mail Express?

USPS Priority Mail Express is the Postal Service's expedited domestic shipping option, guaranteeing delivery in 1 to 3 days by 6 p.m. to most U.S. addresses. It covers packages up to 70 lbs, with a maximum combined length and girth of 108 inches. See USPS's Priority Mail Express page for the full service guarantee.

Because of its speed, Priority Mail Express costs more than standard USPS Priority Mail. You can ship in a free USPS-supplied Flat Rate Envelope or use your own packaging (including branded boxes or mailers) if your shipment does not fit the flat rate options.

How much does USPS Priority Mail Express cost?

Shippo's commercial rates for USPS Priority Mail Express are lower than what you would pay buying postage directly from USPS, with no volume minimums to qualify.

These are Shippo's own commercial rates, pulled July 22, 2026. Flat Rate Envelope prices reflect a shipment from San Francisco, CA (94117) to New York, NY (10013). Weight-based prices reflect a 1-lb package (9 in. x 6 in. x 3 in.) and a 3-lb package (10 in. x 8 in. x 4 in.), both from San Francisco, CA (94117) to San Francisco, CA (94103). Flat Rate Envelope pricing does not change with distance, while weight-based pricing does, so the two rows above are not a direct apples-to-apples comparison. Your rate will vary by your exact origin, destination, weight, and dimensions. Check your own rate with Shippo's shipping calculator before you buy.

What's included: guarantee, insurance and tracking

USPS Priority Mail Express labels typically include:

• A money-back guarantee if USPS misses the promised delivery date and time, subject to exceptions in the Domestic Mail Manual
• USPS tracking
• Up to $100 of insurance for most packages
• The option to add a proof-of-delivery signature record when you buy the label
• Free carrier pickup from your home or business

Sunday and holiday delivery is available in many major markets for an additional fee. Check availability for your specific ZIP codes at checkout.

Flat rate vs. weight-based pricing

You have two ways to price a Priority Mail Express shipment. Flat Rate Envelopes charge one price regardless of weight, as long as the contents fit and the envelope closes flat. That makes them a good deal for dense, heavier items like contracts, small parts, or jewelry. Weight-based pricing uses your own packaging and charges by weight and distance, which usually costs less for light, bulky shipments that would not fit a flat rate envelope. USPS also applies dimensional weight pricing to weight-based packages over 1 cubic foot, billing whichever is greater: actual weight or dimensional weight. Because Flat Rate Envelope pricing does not change by distance while weight-based pricing does, comparing the two directly only makes sense once you know your own route and package size.

For a full breakdown of when each pricing model wins, see USPS Priority Mail vs. USPS Flat Rate: complete cost comparison guide.

USPS Priority Mail Express vs. Priority Mail: which should you use?

Priority Mail Express is the right call when a shipment must arrive within 1 to 3 days by 6 p.m., such as overnight documents, last-minute gifts, or an order with expedited checkout. If your timeline is more flexible, standard USPS Priority Mail typically arrives in 1 to 3 days without the guaranteed time commitment, usually at a lower price. As of July 22, 2026, Shippo's rates for a small Priority Mail flat rate box start at $10.59. Compare your own package against both services with Shippo's shipping calculator before you decide, or see our full USPS Priority Mail vs. Priority Mail Express cost comparison.

Frequently asked questions

Does USPS Priority Mail Express deliver on weekends?

Yes. Sunday and holiday delivery is available in many major markets for an additional fee. Availability depends on your specific origin and destination ZIP codes.

What happens if my package misses its guaranteed delivery time?

You can request a postage refund if USPS misses the guaranteed date and time, as long as you file within 30 days of mailing. Some exceptions apply under the USPS money-back guarantee terms, such as delays caused by an incorrect address.

What's the weight and size limit for Priority Mail Express?

Priority Mail Express allows packages up to 70 lbs, with a maximum combined length and girth of 108 inches.

Is insurance included with Priority Mail Express?

Yes. Most shipments include up to $100 of insurance and USPS tracking at no extra cost, and you can add a proof-of-delivery signature when you purchase the label.

How is Priority Mail Express different from Priority Mail?

Priority Mail Express guarantees delivery in 1 to 3 days by 6 p.m., while standard Priority Mail typically takes 1 to 3 days without a specific time guarantee. Express costs more per label but is the only USPS domestic service backed by a money-back delivery guarantee.

Compare live Priority Mail Express rates with Shippo

Shippo gives you access to rates across 40+ carriers total, including USPS, UPS, FedEx, and DHL, so you can compare Priority Mail Express against other options for speed and cost before you buy. There is no monthly fee and no volume minimum to get started.

Create a free Shippo account and start comparing USPS Priority Mail Express rates today.