USPS, the United States Postal Service, is the national postal service of the United States and an independent federal establishment responsible for delivering mail and packages across the country. Its network serves more than 170 million addresses, reaching cities, suburbs, rural communities, U.S. territories, and military addresses. USPS is largely self-financing through the sale of postage, products, and services rather than relying on tax revenue for its normal operating expenses.
For package delivery within the United States, USPS offers several services aimed at different combinations of speed and cost. Priority Mail Express is its fastest domestic service, with delivery in 1 to 3 delivery days for eligible routes. Priority Mail normally has a 2 to 3 day service standard, while USPS Ground Advantage provides economical package delivery in approximately 2 to 5 business days. Media Mail is another lower-cost option for qualifying books, recordings, and other eligible media, with a typical service standard of 2 to 8 days.
USPS also provides useful shipping tools for individuals and businesses. Customers can buy postage and create labels with Click-N-Ship, schedule eligible Package Pickup service from a home or business, use Post Office locations, and receive information about incoming packages through Informed Delivery. USPS Tracking is included with many popular package services, including USPS Ground Advantage and Priority Mail, allowing senders and recipients to follow a package as it moves through the postal network.
Internationally, USPS connects the United States with postal networks in more than 180 countries. Important international options include Priority Mail Express International, with an estimated 3 to 5 business day delivery standard, and Priority Mail International, which normally has an estimated 6 to 10 business day standard. International package tracking is available with many services, although the amount of tracking information and service availability can vary by destination country.
How to track USPS packages
The easiest way to track a USPS package is through 4tracking.net. Enter your USPS tracking number in the tracking field and start the search. 4tracking is a universal package tracking service, making it useful when you receive USPS packages as well as packages handled by other postal and courier companies. Available tracking events can show when shipping information was created, when USPS accepted the package, movement between processing facilities, arrival at the destination facility, an attempted delivery, delivery, or another exception affecting the package.
You can also track a package directly through the official USPS Tracking service. USPS scans the barcode on a trackable package at different stages of its journey. Tracking can begin when the sender electronically notifies USPS that a package is expected, continue when USPS physically accepts and processes it, and finish when the package is delivered or collected by the recipient or an authorized person. USPS states that scanning information is updated throughout the day as new scans become available.
USPS provides several other ways to follow package tracking. You can request eligible email or text updates after entering the tracking number, send the tracking number by text message to 28777 (2USPS), use the USPS mobile service, or use Informed Delivery to view many incoming packages associated with your address. Some eligible packages also support USPS Delivery Instructions, which can provide options for where the carrier should leave the package or whether it should be sent to a Post Office.
Keep in mind that tracking does not make a package move faster and is not itself a delivery guarantee. A tracking page may also show an Expected Delivery Window, which USPS describes as a two-hour period when the package may arrive. That time window is an estimate rather than a guarantee, and the package may still be delivered later in the day.
USPS tracking number formats
USPS uses several tracking-number formats depending on the service. Many domestic USPS packages have long numeric tracking numbers. The official USPS Tracking page shows a standard USPS Tracking example as 9400 1000 0000 0000 0000 00, while a Priority Mail example is 9205 5000 0000 0000 0000 00. These spaces are shown for readability on the USPS example; shipping labels commonly display the digits beneath a barcode.
Other official examples include Certified Mail as 9407 3000 0000 0000 0000 00, Signature Confirmation as 9202 1000 0000 0000 0000 00, and Registered Mail as 9208 8000 0000 0000 0000 00. Priority Mail Express can use a long numeric number such as 9270 1000 0000 0000 0000 00 or an international-style identifier such as EA 000 000 000 US.
USPS international packages often use the standardized postal format of 2 letters + 9 digits + 2 letters. Official USPS examples include EC 000 000 000 US for Priority Mail Express International and CP 000 000 000 US for Priority Mail International. International Registered Mail can use a format such as RA 000 000 000 US, while some First-Class international services can use identifiers beginning with letters such as LX.
If your USPS tracking number does not work, check that you copied the entire number from the mailing receipt, shipping label, USPS confirmation email, or retailer's shipping confirmation. Do not confuse the tracking number with an online store's order number. USPS also notes that local Post Offices and Customer Care agents generally cannot recover a lost tracking number, so recipients who do not have it should normally ask the sender.
How long does USPS delivery take?
USPS delivery time depends primarily on the service selected, the origin and destination ZIP Codes, when the package was accepted, and whether weather or other transportation problems affect the route. Priority Mail Express is the fastest mainstream domestic option and offers delivery in 1, 2, or 3 delivery days depending on the origin, destination, and acceptance date. Eligible Priority Mail Express packages are scheduled for delivery by 6 p.m. on the scheduled delivery day, subject to the service's rules and exceptions.
For a typical domestic example, a Priority Mail package has an expected service standard of approximately 2 to 3 days. USPS Ground Advantage normally takes approximately 2 to 5 business days, making it a practical choice when the package is not urgent. A qualifying Media Mail package, such as a box of eligible books, normally has a service standard of approximately 2 to 8 days. These standards are expected delivery times rather than guaranteed arrival dates, except where a specific guaranteed service applies.
For international packages, Priority Mail Express International provides a useful faster example, with an expected delivery standard of approximately 3 to 5 business days to about 180 countries where the service is available. Priority Mail International is slower but more economical, with an expected standard of approximately 6 to 10 business days. Actual international delivery can take longer because customs processing is outside the normal transportation time and destination-country conditions can affect final delivery.
Not every package will fit neatly within these time ranges. USPS notes that weather, natural disasters, traffic, staffing conditions, route changes, and other unusual circumstances can affect delivery. USPS Ground Advantage packages going to certain destinations, including Alaska, Hawaii, and offshore locations, or packages containing certain hazardous materials or live animals, can also receive slower service.
Understanding USPS tracking updates
A tracking update near the beginning of the journey may simply mean that USPS has received electronic information about an expected package. Once the package is physically accepted, further scans can appear as it moves through the USPS network. A package can pass through several processing and distribution facilities before arriving at the facility responsible for its final delivery.
Tracking does not necessarily update continuously while the package is traveling. USPS says scans are recorded at different points throughout the mailstream and tracking information is updated as those scans become available. A gap of several hours or even longer therefore does not by itself prove that the package is lost.
International USPS tracking can have longer gaps because more than one postal operator may be involved. A package can leave the United States and receive its next meaningful update after being processed by the destination country's postal system or customs authority. Tracking is included with many international products, but USPS notes that destination restrictions can affect the information available.
How to contact USPS about a package
If there is a problem with a USPS package, start by checking the latest tracking status. For domestic and international USPS Tracking issues, USPS lists 1-800-222-1811. Current hours are Monday through Friday from 8:00 a.m. to 8:30 p.m. Eastern Time and Saturday from 8:00 a.m. to 6:00 p.m. Eastern Time. USPS notes that customer service representatives generally see the same tracking information displayed on the public USPS Tracking page, but they can assist with other package-related issues.
For general USPS customer service, you can call 1-800-ASK-USPS (1-800-275-8777). USPS also provides online customer service options and local Post Office assistance. If the package came from an online store, contact the seller or sender as well, especially if you need the tracking number, proof of mailing, shipping-service details, or help opening a claim.
If a domestic package appears to be missing, USPS recommends checking tracking first. A Missing Mail search request can generally be submitted starting 7 days after mailing. USPS asks for information such as the sender and recipient addresses, tracking number if available, mailing date, packaging details, a description of the contents, and photographs that could help identify the package.
If a package was insured and is lost, damaged, or has missing contents, a claim may also be available depending on the service and circumstances. USPS advises filing claims for damaged or missing contents promptly, and its Missing Mail guidance states that these claims must be filed no later than 60 days from the mailing date. For international packages, inquiry and claim procedures depend on the service and whether the package was sent from or to the United States.
Frequently asked questions about USPS package tracking issues
Why is my USPS tracking number not working?
The sender may have created the package information recently and the first USPS scan may not yet be available. Confirm that you entered the USPS tracking number rather than the retailer's order number and check every digit or letter carefully. If you are the recipient and do not have the number, USPS recommends asking the sender because USPS customer service generally cannot recover a lost tracking number.
Why has my USPS package tracking stopped updating?
A package can continue moving while no new scan is visible. USPS packages are scanned at different points in the postal network, and information is updated as scans become available. Wait for the next processing event and compare the elapsed time with the delivery standard for the service used. If the expected period has been substantially exceeded, follow the USPS help process for delayed or missing packages.
Why does USPS show that my package is still in transit?
An in-transit package is generally still moving through the USPS network toward its destination. It may be traveling between processing facilities without a new public scan. Weather, transportation conditions, unusually high volumes, route changes, or other operational circumstances can also extend the time between updates.
My USPS package says delivered, but I cannot find it. What should I do?
Check the tracking details for the recorded delivery location, because USPS tracking can sometimes indicate whether a package was delivered to a mailbox, reception desk, neighbor, or another location. Check around the delivery address and ask household members or staff who may have accepted it. If it still cannot be located, contact USPS and notify the sender or retailer so the appropriate investigation can be started.
Can every USPS package be tracked?
No. USPS Tracking is available with most domestic package products and many international services, but not every USPS item includes tracking. For example, ordinary First-Class Mail postcards, letters, and flats do not qualify for standard USPS Tracking, although some extra services such as Certified Mail or Registered Mail can provide barcode-based tracking information.
How long should I wait before reporting a USPS package as missing?
First compare the package's progress with the normal service standard. Priority Mail Express is generally 1 to 3 delivery days, Priority Mail approximately 2 to 3 days, and USPS Ground Advantage approximately 2 to 5 business days. If the package remains missing, USPS allows a Missing Mail search request to be submitted starting 7 days after the mailing date.
Can I track an international USPS package?
Yes, many USPS international services support tracking. Priority Mail Express International and Priority Mail International include USPS Tracking, subject to destination-specific restrictions. International tracking may continue through the destination postal operator after the package leaves the United States, so updates can sometimes take longer to appear.
Can I track USPS packages on 4tracking?
Yes. Enter your USPS tracking number on 4tracking.net to track the package and view available delivery updates. Because 4tracking supports many postal and courier companies, it is particularly convenient when you receive USPS packages alongside packages handled by other carriers and want to use one package tracking service.
Who should I contact if my USPS package appears lost or damaged?
Contact USPS and the sender or retailer as soon as the problem becomes clear. For tracking-related assistance, USPS lists 1-800-222-1811. If the package is missing, a Missing Mail search may be available, and insured packages may qualify for a claim. Keep the mailing receipt, tracking number, photographs, packaging, and proof of value because these can be needed during an investigation or claim.
Monthly Delivery Performance for USPS – August 2026
Our comprehensive monthly delivery report for USPS in August 2026 is based exclusively on shipments confirmed as delivered, detailing the fastest, average, and slowest transit times from origin to destination. Shipments still in transit are excluded to ensure accurate and reliable insights.
| From | To | Delivery Time |
|---|---|---|
 UnknownUnknown |  USAUnited States |
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| Unknown Unknown |  ITAItaly |
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| Unknown Unknown | Unknown Unknown |
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| Unknown Unknown |  DEUGermany |
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| Unknown Unknown |  GBRUnited Kingdom |
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| Unknown Unknown |  CANCanada |
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| Unknown Unknown |  ESPSpain |
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| Unknown Unknown |  CHESwitzerland |
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| Unknown Unknown |  ROURomania |
|
 CHNChina | USA United States |
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| USA United States | USA United States |
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| Unknown Unknown |  POLPoland |
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| Unknown Unknown |  BRABrazil |
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| Unknown Unknown |  FRAFrance |
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| Unknown Unknown |  GRCGreece |
|