Skip to main content

How the U.S. Post Office Works and What Services Are Available

By Constance Obi · Culture & Recreation Writer

What the U.S. Post Office does and who runs it

The United States Postal Service (USPS) is a federal agency that delivers mail and packages to every address in the country, including rural areas where private carriers often do not go. It operates independently from other government departments and funds itself through postage sales and services rather than tax dollars. USPS handles roughly 470 billion pieces of mail each year and maintains post offices in nearly every town and city across South Carolina.

The agency was established in 1971 to replace the cabinet-level Post Office Department. Today it is governed by a Postmaster General and a Board of Governors, with local postmasters running individual offices. In South Carolina, USPS operates hundreds of locations, from full-service branches in cities like Charleston and Columbia to smaller rural stations in towns like Beaufort and Aiken.

Key Takeaways

  • USPS delivers mail and packages to every U.S. address six days a week, including places private carriers skip.
  • You can mail letters, packages, and documents at any post office, and USPS offers tracking, insurance, and signature confirmation for additional fees.
  • Post offices also sell stamps, money orders, and passport application services, and some locations offer notary services.
  • Delivery times vary by service: First-Class Mail takes one to three business days, Priority Mail takes one to three days, and Priority Mail Express is overnight or two-day.
  • You can track packages online, file complaints about service, and look up post office hours and locations through USPS.com.

Mailing letters and packages: services and costs

USPS offers several mailing options depending on speed and weight. First-Class Mail is the standard service for letters and small packages under 13 ounces; it typically arrives within one to three business days and costs less than other services. Priority Mail handles larger packages and guarantees delivery in one to three business days. Priority Mail Express is the fastest option, delivering overnight or within two business days to most addresses.

For items of high value or importance, you can add Certified Mail (which provides proof of delivery), Return Receipt (a signed confirmation from the recipient), or Insurance (coverage up to $5,000 for loss or damage). Prices vary based on weight, distance, and the service chosen. You can purchase postage at any post office, online through USPS.com, or through a postage meter if you mail frequently.

Services beyond mailing: stamps, money orders, and documents

Post offices sell Forever Stamps, which remain valid for First-Class Mail postage regardless of future price increases, as well as standard stamps in various denominations. They also issue money orders, which function as a secure way to send cash through the mail; money orders can be purchased for a small fee and tracked if lost.

Many post offices provide passport application services. You can apply for a new passport, renew an existing one, or request a replacement at designated locations. Some post offices also offer notary services, though availability varies by location. Call ahead to confirm whether your local post office provides notary services, as not all branches do.

Tracking packages and understanding delivery times

When you mail a package with Priority Mail or Priority Mail Express, USPS provides a tracking number. You can enter this number on USPS.com to see real-time updates on where your package is and when it will arrive. First-Class Mail packages also come with tracking at no extra charge. For added peace of mind, Certified Mail and insured packages show detailed delivery confirmation.

Delivery times depend on the service and destination. First-Class Mail typically takes one to three business days within South Carolina and slightly longer to other states. Priority Mail usually arrives within one to three business days nationwide. Priority Mail Express guarantees overnight delivery to most addresses or your money back. Weather, holidays, and mail volume can affect these timelines, particularly during peak seasons like December.

Finding your local post office and checking hours

USPS.com has a Post Office Locator tool where you enter your zip code or address and see all nearby locations, hours, and services offered. Most full-service post offices are open Monday through Friday and Saturday mornings; hours vary by location. Some smaller branches operate limited hours or share space with other businesses like grocery stores.

In South Carolina, major post offices in Charleston, Columbia, Greenville, and Spartanburg typically have extended hours and full services. Rural post offices may have shorter hours or close for lunch. If you cannot visit during regular hours, you can purchase postage online and use USPS package drop boxes, which are available 24/7 at many locations.

Reporting problems and filing complaints

If mail arrives damaged, late, or goes missing, you can file a complaint through USPS.com or visit your local post office in person. For lost or damaged packages, USPS investigates and may issue a refund if the item was insured. For service complaints—such as late delivery or mail not being delivered at all—you can contact USPS directly or reach out to your local postmaster.

The USPS Customer Service phone line is available to answer questions about services, pricing, and delivery. For serious or ongoing issues, you can escalate complaints to the USPS Office of Inspector General, which investigates fraud and service failures. Keep tracking numbers, receipts, and photos of damaged items when filing a complaint, as these help speed up the investigation.

Frequently Asked Questions

Can I mail cash through the post office?

Mailing cash is not recommended because it cannot be tracked or insured. Instead, use a money order, which you can purchase at any post office for a small fee. Money orders can be tracked and replaced if lost, making them a safer way to send money through the mail.

What is the difference between Priority Mail and Priority Mail Express?

Priority Mail takes one to three business days and costs less; Priority Mail Express guarantees overnight or two-day delivery and costs more. Choose Priority Mail for items that are not urgent and Priority Mail Express when speed is essential.

Do I need to go to the post office to mail a package?

No. You can print a shipping label online through USPS.com, attach it to your package, and drop it in a blue USPS mailbox or at a package drop box. You only need to visit the post office if you want to weigh the package first or purchase postage in person.

What happens if my package is lost?

File a claim through USPS.com using your tracking number. If the package was insured, USPS will investigate and may issue a refund. Without insurance, USPS is not liable for loss. This is why insurance is worth considering for valuable items.

Can I hold mail at the post office while I am away?

Yes. You can request a mail hold through USPS.com or by visiting your local post office. The hold typically lasts up to 30 days. When you return, you can pick up your held mail at the post office or request that delivery resume.