USPS

The United States Postal Service (USPS) is an independent agency of the US federal government and the country's primary postal operator. Mandated by the Postal Service Act of 1970, USPS provides universal postal service to every address in the United States — approximately 167 million delivery points — six days a week, at uniform rates regardless of distance or remoteness.

By the Numbers

USPS is one of the largest civilian employers in the United States:

• 600,000+ career employees plus hundreds of thousands of non-career workers
• 228,000+ vehicles — the largest civilian vehicle fleet in the world
• ~139 billion pieces of mail and packages delivered annually
• 31,000+ post office locations across all 50 states and territories
• $78.2 billion in operating revenue (FY2023)

Despite its scale, USPS has faced persistent financial challenges due to declining first-class mail volume (down ~40% over the past 15 years), congressional mandates, and legacy pension obligations.

Key Shipping Services

Priority Mail Express: USPS's fastest domestic service, with 1–2 day guaranteed delivery and flat-rate pricing. Includes free pickup, $100 insurance, and tracking.

Priority Mail: 1–3 business day delivery with flat-rate boxes and envelopes. A favorite for e-commerce due to no fuel surcharges and free packaging.

USPS Ground Advantage: Introduced in 2023, consolidating First-Class Package Service and Parcel Select into a single 2–5 day ground service. Highly competitive for lightweight packages under 1 lb.

Media Mail: Deeply discounted rate for books, CDs, DVDs, and educational materials. No time guarantee, but very cost-effective for eligible content.

USPS for E-Commerce

USPS handles the final mile for a significant portion of US e-commerce deliveries — including many FedEx SmartPost and UPS SurePost packages that inject into the postal network for last-mile delivery. For direct-to-consumer brands shipping lightweight packages to residential addresses, USPS often offers the lowest all-in cost due to no residential delivery surcharges and no fuel surcharges.

Tracking

USPS tracking numbers are 20–22 digits (typically starting with 9 for domestic services). Tracking updates are available at usps.com, the USPS mobile app, and via Informed Delivery — a free service that sends daily email previews of mail arriving at your address.

For more information on how to track shipments and manage your deliveries, use our tracking form.