USPS Fuel Surcharge: How the Weekly Charge Works From January 2027

Updated November 2026.

Starting in January 2027, USPS adds a fuel surcharge to its package services. It is a percentage of base postage, it changes every week with diesel and jet fuel prices, and it applies to USPS Ground Advantage, Priority Mail, Priority Mail Express and Parcel Select, whether you buy postage at the counter or through a shipping platform. USPS has not yet published the first percentage, the table that turns a fuel price into a percentage, or the exact January day. What it has published is the mechanism, and the mechanism is what decides how the charge will land on your labels.

What USPS has announced

The source is a two-page USPS fuel surcharge FAQ on PostalPro, published in October 2026. In USPS's words, the surcharge "will be charged on all competitively priced packages and calculated as a percentage of the base postage," and it "will be updated weekly, based on the prices of diesel and jet fuel, as described on the eia.gov website." The rest of the FAQ fills in the details that matter to someone paying for labels:

• Start: "January 2027." No day is given.
• Who pays it: commercial shippers and retail customers. A parcel paid for at the Post Office counter carries it too.
• How often it changes: weekly.
• Where it applies: domestic shipments only.
• What it is charged on: base postage, not extra services or nonstandard fees.
• Notice: USPS says it will publish each percentage three to four days ahead for the jet-fuel services and three to five days ahead for the diesel services, with current and upcoming percentages and effective dates sent to shippers electronically and historical data posted publicly.
• Stale postage: a parcel paid with an outdated surcharge amount "will be postage due."

Which services it applies to, and which fuel price moves each one

USPS ties each product to one of two fuel prices, and it names the return services it covers.

The FAQ lists Priority Mail Express Return, Priority Mail Return and Ground Advantage Return by name. It lists Parcel Select on its own, so whether a Parcel Select return label carries the surcharge is not something USPS has said.

That split matters because diesel and jet fuel do not move together. A brand that ships everything Ground Advantage will see one weekly number; a brand that mixes Priority Mail and Ground Advantage will see two, and they can move in different directions in the same week. First-Class Mail, Media Mail and other market-dominant products are not in USPS's list; the FAQ limits the surcharge to competitive package products.

USPS points to eia.gov for the fuel prices without naming the exact series. FedEx and UPS base their own surcharges on the weekly national on-highway diesel average and the U.S. Gulf Coast jet fuel spot price from the same agency, so it is reasonable to expect USPS to follow something similar, but treat that as a guess until USPS publishes its table.

Base postage only: the detail that separates USPS from UPS and FedEx

The percentage is applied to base postage and nothing else. If you add Signature Confirmation, insurance, or get hit with a nonstandard size fee, those amounts are not multiplied by the fuel percentage. That is a narrower base than the private carriers use. FedEx assesses its Ground fuel surcharge on the net package rate plus a list of surcharges that includes the Residential Delivery Charge, Delivery Area Surcharge, Additional Handling and Oversize charges. UPS applies fuel to the transportation charge plus a published list of accessorials including Delivery Area Surcharges, Additional Handling, Large Package and Demand Surcharges.

So two shipments with the same fuel percentage can carry very different fuel dollars. On a UPS or FedEx parcel, fuel is assessed on the base charge plus whichever of those listed surcharges apply, within each carrier's service and account terms; UPS, for example, does not apply its domestic Ground fuel surcharge to Ground packages shipped at retail rates from the contiguous United States. On a USPS parcel it is one percentage times the base postage, full stop. That is also why the UPS and FedEx weekly percentages are not a preview of USPS's. They are built on different bases, and USPS has not said where its scale will start.

How much it adds to a package

Until USPS publishes a percentage, the only honest answer is arithmetic. Take a 1 lb USPS Ground Advantage commercial label to zone 5, which is $9.29 under the Notice 123 prices in effect through January 17, 2027. Every percentage point of fuel surcharge adds about nine cents to that label.

These rows are not a forecast. They show the shape: a 1 lb label moves about a dime per point, a $20 label moves about twenty cents per point, and the number resets every week. The $9.29 is also a time-limited price: the increases in that Notice 123 are scheduled to end on January 17, 2027, and USPS has not posted January 2027 price files on Postal Explorer. What base postage will be in January, and how its timing lines up with the surcharge, is not yet known. Retail postage for the same parcel is $11.70, and a percentage applied to a higher base adds proportionally more. If you want to check the zone for your own lanes, the USPS zone map covers it.

For context on how far a fuel surcharge can run, FedEx Ground's rate was 29.25% for the week of November 2, 2026. That is FedEx's number on FedEx's base. USPS has made no statement about its own level.

Where the 8% fits

This surcharge is not the first time USPS has priced fuel into postage this year. In March, USPS announced an 8% time-limited increase on base postage for Priority Mail Express, Priority Mail, Ground Advantage and Parcel Select, running from April 26, 2026 until midnight Central Time on January 17, 2027. The release called that increase "a necessary bridge to a permanent mechanism to reflect market conditions in prices for competitive products," and said the 8% was "less than one-third of what our competitors charge for fuel alone."

Put the two documents side by side and the sequence is clear: the flat 8% is scheduled to end on January 17, and a weekly surcharge begins in January. What USPS has not said, in either document, is that one replaces the other on a particular day, or that the first weekly percentage will be anywhere near 8%. News coverage that describes the surcharge as "permanent" is borrowing the March release's phrase about a permanent mechanism; the FAQ itself does not use the word. The dated timeline of USPS's 2026 and 2027 price changes, including the holiday prices that also end January 17, is in the USPS price increase guide.

What USPS has not published yet

A short list, because the gaps are where the guesswork starts:

• The exact start day in January. January 17 is the end of the 8% and the holiday prices, not an announced start for the surcharge.
• The first percentage and the table that maps a fuel price to a percentage.
• Which EIA series USPS will read for diesel and for jet fuel.
• How shipping platforms will display it. USPS says all of its payment systems and its Pricing, Domestic Labels, International Labels and PMOD APIs will apply the fee when it is in effect, and that it expects testing to be available about two weeks before the price change. How that shows up in Shopify Shipping, Pirate Ship, ShipStation or eBay labels is up to each platform.
• Negotiated Service Agreement terms. USPS says NSAs "may have customized language," so a brand with a negotiated contract should read its own.

What to do if you ship with USPS

USPS has not said how big the surcharge will be, but it changes weekly and it lands on every domestic label for the four services above. A few things worth doing now rather than in January:

1. Budget a fuel line on USPS postage. You already do this for UPS and FedEx. Put a placeholder percentage against your USPS spend so January's number lands in a line you expected instead of as a surprise on the invoice.
2. Watch the testing window. USPS says changes are usually available for testing two weeks before a price change date. If you use a label platform, that is a good time to ask how it plans to show the surcharge.
3. Mind label timing. USPS says parcels carrying an outdated surcharge amount will be postage due. A label bought ahead of a weekly change and mailed after it is the obvious risk. Ask your label platform how it handles labels printed before a weekly change and shipped after.
4. Re-compare carriers in February, not January. Ground Advantage has no residential surcharge and the fuel surcharge is on base postage only, so a light residential parcel may stay cheaper on USPS even with fuel added. But a comparison made on week one's percentage will be stale by week two. Run it on a few weeks of invoices. UPS Ground versus USPS Ground Advantage has the service-level tradeoffs.
5. Separate the surcharge from base postage. The time-limited increase is scheduled to end on January 17, 2027, USPS has not posted January base prices, and the surcharge starts sometime in January. When a label cost changes, it helps to know whether base postage or the fuel line moved it.

If you are comparing 3PL quotes

A fuel surcharge does not go away when a 3PL ships your orders; it shows up in how postage is billed. Ask two questions of any quote: is postage included in the per-order price or billed separately, and how do carrier surcharges, now including a weekly USPS fuel surcharge, show up on the invoice. A 3PL that bills postage at cost should be able to show the surcharge as its own line; ask whether it will. A 3PL that quotes a per-order rate with postage included sets that rate against the same postage tables.

At Simpl, the flat per-order rate includes postage; carrier surcharges, when they apply, are billed per our terms. Every fee is disclosed. How postage fits into Simpl's per-order rate has the detail, and the pricing page has the current terms.

We're a 3PL, so we have a stake in how brands think about postage. The USPS rules above come from USPS's own documents and do not depend on it.

Sources

• USPS PostalPro, Frequently Asked Questions: USPS Fuel Surcharge Implementation, October 2026: the mechanism, products, fuel indexes, base-postage scope, notice periods, API and postage-due answers.
• USPS, USPS announces transportation-related time-limited price change, March 25, 2026: the 8% increase, its April 26 to January 17 window, and the "bridge to a permanent mechanism" language.
• USPS Postal Explorer, Price Change and the Time-Limited 2026 Notice 123: current Ground Advantage prices and the January 17, 2027 end date.
• FedEx, Fuel surcharges: FedEx's weekly rates, fuel indexes and the surcharges its fuel charge applies to.
• UPS, Fuel surcharges: UPS's weekly diesel and jet fuel indexes, the services each surcharge applies to, and the retail-rate Ground exemption.
• UPS, Value-Added Services and Other Charges with Fuel Surcharge Application: the accessorials UPS applies fuel to.
• U.S. Energy Information Administration, Gasoline and Diesel Fuel Update and spot prices: the weekly diesel and jet fuel prices carriers reference.