A shipper number is the account number a carrier assigns to a business or person who ships with it, and the term most often means a UPS shipper number: the six-character alphanumeric UPS account number, such as A1B2C3, that identifies who created and pays for a shipment. It appears on UPS invoices as “Shipper Number” and forms characters 3 through 8 of every 1Z UPS tracking number created on that account.
Other carriers use different identifiers. FedEx calls it an account number, and USPS has no single shipper number at all, relying instead on business IDs like the Mailer ID. This guide explains how each one works, where to find yours, and how it differs from a tracking number.
What Does a Shipper Number Do?
A shipper number links every label to the account that created it, so the carrier knows whom to bill, which negotiated prices apply and who to contact about a problem. It is the identity of the shipping account, not of an individual package.
- Billing: charges for transportation, surcharges and adjustments post to the shipper number’s account.
- Pricing: any discounts the account has negotiated are attached to the number.
- Pickups and services: scheduled pickups, returns and third-party billing all reference an account number.
- Problem resolution: claims, address corrections and invoice disputes are handled against the account.
Because the number controls billing, carriers penalize mistakes. The UPS Tariff/Terms and Conditions of Service includes a Missing/Invalid Account Number fee for shipments billed to an account number that is missing or incorrect, including the shipper’s own.
How Is a Shipper Number Different From a Tracking Number?
A shipper number identifies the account and stays the same on every shipment, while a tracking number identifies one package and is never reused. UPS connects the two: a standard UPS tracking number is 18 characters long and built from the shipper number.
| Characters in a 1Z tracking number | Meaning | Example |
|---|---|---|
| 1–2 | “1Z” prefix used on UPS small-package tracking numbers | 1Z |
| 3–8 | Shipper number (UPS account number) | A1B2C3 |
| 9–10 | Service level code | Two digits for the UPS service |
| 11–17 | Package identifier assigned by the shipper’s system | Seven digits |
| 18 | Check digit | One digit |
This structure means you can often read the shipper number straight off a UPS tracking number, which is how many businesses find a forgotten account number. Our UPS package tracking number guide explains the other UPS tracking formats.
How Do UPS, FedEx and USPS Shipper Numbers Compare?
Each carrier issues its own account identifier, and none of them work across carriers. A business that ships with all three has three separate numbers.
| Carrier | What it’s called | Format | Where it appears |
|---|---|---|---|
| UPS | Shipper number / UPS account number | 6 alphanumeric characters | Invoices, account summary on ups.com, characters 3–8 of 1Z tracking numbers |
| FedEx | FedEx account number | Usually 9 digits | Invoices and the FedEx account profile; not part of the tracking number |
| USPS | No single shipper number; business IDs such as the Mailer ID (MID) and Customer Registration ID (CRID) | MID is 6 or 9 digits | Business Customer Gateway; the MID is encoded in Intelligent Mail barcodes |
Does USPS use shipper numbers?
USPS doesn’t assign a shipper number to retail customers, so you can buy postage at the counter or on usps.com without one. Businesses that mail in volume get identifiers through the USPS Business Customer Gateway: a Customer Registration ID for the business location and a Mailer ID that appears in the barcodes on letters, flats and package labels. Those IDs serve the same purpose as a UPS shipper number, tying each mailpiece to the business that sent it.
How Do You Get a Shipper Number?
You get a UPS shipper number by opening a UPS account on UPS.com; the number is assigned when the account is created. You’ll need your business or personal details, a billing address and a payment method.
- Create a ups.com login with your contact details.
- Open a shipping account and choose how to pay: card or invoice billing.
- Note your six-character account number, shown in the account summary once the account is open.
- Link the number to the software or website where you print labels.
A FedEx account number comes from opening an account on FedEx.com, and USPS business IDs come from registering in the Business Customer Gateway on USPS.com. If you’re shipping your first box, our guide on how to ship a package covers the steps around the label.
Where Can You Find Your UPS Shipper Number?
The fastest place to find a lost shipper number is an old UPS invoice, where it’s labeled “Shipper Number.” You can also find it in these places:
- The account summary or payment settings after you log in to ups.com.
- Characters 3 through 8 of any 1Z tracking number from a shipment you created.
- The settings page of the shipping software or marketplace connected to your UPS account.
- UPS customer service, after it verifies that you own the account.
What Are Common Shipper Number Problems?
Most problems come from using the wrong account on a label, which sends the bill somewhere unexpected or triggers a fee. These are the ones to watch for:
- Invalid shipper number errors: software rejects a number that’s mistyped, closed or not activated for the service you selected.
- Billing to the wrong account: a receiver or third-party account number entered for billing must be valid, or UPS can rebill the charges and add its Missing/Invalid Account Number fee.
- Multiple locations: businesses with several warehouses often keep a separate number per location so pickups and invoices stay organized.
- Confusing it with customs IDs: a shipper number isn’t an EIN, an EORI number or a tax ID, and international shipments may need those in addition to the account number.
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Frequently Asked Questions
What is a shipper number on a UPS label or invoice?
A shipper number on UPS paperwork is your six-character alphanumeric UPS account number. It identifies the account that created and pays for the shipment, appears on invoices labeled “Shipper Number,” and is embedded as characters 3 through 8 of every 1Z tracking number created on that account.
Is a shipper number the same as a tracking number?
No. A shipper number identifies your shipping account and stays the same on every package, while a tracking number identifies one shipment. With UPS the two are related: an 18-character 1Z tracking number contains the six-character shipper number, a service code, a package identifier and a check digit.
Can I use one shipper number with every carrier?
No. Each carrier issues its own account identifier. UPS uses a six-character shipper number, FedEx uses a separate account number that is usually nine digits, and USPS uses business IDs such as the Mailer ID and Customer Registration ID. A business that ships with all three carriers keeps three separate numbers.
Do I need a shipper number to send a package with USPS?
No. USPS doesn’t require a shipper number for retail customers, so you can buy postage at a Post Office or on usps.com without one. Businesses that mail in volume register in the USPS Business Customer Gateway, which issues a Customer Registration ID and a Mailer ID that appears in their barcodes.
Sources
- UPS Tariff/Terms and Conditions of Service (United States): Missing/Invalid Account Number fee and third-party billing
- UPS.com: opening a UPS account
- FedEx.com: opening a FedEx account
- USPS.com: Business Customer Gateway
Part of our Packing Slip guide. Related: Dymo vs Zebra, Do I Need a Special Printer to Print Postage at Home, Abbreviation for Shipping.
