What Is a Freight Fuel Surcharge?
A fuel surcharge (FSC) is a variable percentage added on top of the base linehaul rate for every LTL shipment. It exists because diesel is the single largest operating cost for trucking, and fuel prices swing 20–40% year to year. Carriers pass that volatility directly to shippers rather than baking it into a fixed rate.
The FSC appears as a separate line item on your freight invoice and typically runs 10–25% of the base linehaul rate — though it has exceeded 30% during diesel price spikes. It is updated weekly by most major carriers and applied uniformly to all shipments regardless of lane or commodity.
Unlike accessorial charges, FSC cannot be waived on individual shipments. For high-volume shippers it can be discounted as part of a volume contract, but spot market shipments pay the full published rate every time.
How the EIA Diesel Index Drives Your Rate
The U.S. Energy Information Administration (EIA) publishes the national average retail price for on-highway diesel fuel every Monday. Major LTL carriers — including UPS Freight and FedEx Freight — use this figure as the input to their fuel surcharge tables. The process: the EIA posts Monday's price, carriers look it up in their published sliding scale, and the resulting percentage applies to all shipments tendered that week.
There is always a one-week lag. A shipment on Wednesday is subject to the FSC set by the EIA price published the prior Monday. That EIA figure itself reflects fuel prices from the previous week, so in practice your surcharge reflects diesel prices 7–14 days old. You can track the current EIA national diesel price and live carrier FSC rates on our tracker.
FSC CALCULATION FORMULA
FSC % → Lookup: EIA diesel price → carrier sliding scale table
Dollar amount:
FSC $ = Base Linehaul Rate × FSC %
Example:
Base linehaul: $400.00
EIA diesel (Mon): $3.52/gal
Table lookup: $3.50–$3.74 → 18.5%
FSC charge: $400.00 × 18.5% = $74.00
The FSC Sliding Scale
Carriers publish a tiered table that maps each EIA diesel price range to a surcharge percentage. The tiers are typically set in $0.05–$0.25 increments. The higher the diesel price, the higher the surcharge. Below is a representative excerpt showing how the scale works. Actual published tables vary by carrier and are updated periodically — always verify against the carrier's live table.
| EIA Diesel ($/gal) | Approx FSC % | Cost Impact |
|---|---|---|
| $2.50–$2.74 | ~8–10% | Low |
| $2.75–$2.99 | ~10–12% | Low |
| $3.00–$3.24 | ~12–14% | Below Avg |
| $3.25–$3.49 | ~15–17% | Average |
| $3.50–$3.74 | ~17–19% | Above Avg |
| $3.75–$3.99 | ~19–21% | High |
| $4.00–$4.24 | ~21–23% | Very High |
| $4.25–$4.49 | ~23–25% | Very High |
| $4.50+ | 25%+ | Highest |
Representative values only. Actual carrier tables differ and change. UPS and FedEx publish their current tables in their tariff documentation.
See this week's live EIA diesel price and current carrier FSC rates.
Live FSC Tracker →How FSC Stacks on Your Invoice
FSC applies to the base linehaul rate only — not to accessorial charges. Liftgate, residential delivery, address correction, and similar fees are charged on top of the linehaul-plus-FSC subtotal. This means a single reclassification hits you twice: the base rate rises, and the FSC dollar amount rises proportionally with it.
If your carrier bumps your freight class from 85 to 100, a $400 linehaul might become $580 — and your FSC jumps from $74 to $107 at the same 18.5% rate. You're paying more on both lines simultaneously.
SAMPLE LTL INVOICE LINE ITEMS
UPS vs FedEx: Why Their Rates Differ
Both UPS Freight and FedEx Freight peg their FSC to the EIA national on-highway diesel average. But their tables are not identical. FedEx Freight applies regional diesel averages for some lanes, using EIA regional series rather than the national figure. UPS uses the national average uniformly across all lanes. This means two identical shipments on the same route can carry different FSC percentages depending on which carrier you use.
Regional LTL carriers (Estes, Old Dominion, Saia, XPO) each maintain their own FSC tables with their own tier thresholds. Some use the national EIA index, others use regional averages, and a few use their own proprietary fuel indexes. Always confirm which index your contract references.
UPS FREIGHT vs FEDEX FREIGHT — FSC METHODOLOGY
5 Common Fuel Surcharge Overcharges
Most FSC errors are not fraud — they're billing system errors, wrong tariff lookups, or misapplied tables. But they still cost you money. Here's what to look for on every invoice.
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01
FSC applied to incorrect base rate
If the carrier uses a higher base rate than contracted — or your freight was reclassified — your FSC dollar amount rises proportionally. The percentage looks right; the dollar amount is inflated.
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02
Wrong EIA week applied
Carriers should apply the FSC from the Monday before your ship date. Manual billing errors occasionally use the wrong week's rate. A $0.15/gal difference translates to 1–2% FSC change — real money on large invoices.
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03
FSC charged on accessorial fees
Fuel surcharge should only apply to linehaul. Watch for FSC appearing on liftgate, residential, or inside delivery line items. It shouldn't be there — and most carriers will credit it if you flag it.
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04
Regional index when national was contracted
If your carrier uses a regional EIA average (which can run $0.10–$0.20 higher than national in some zones) and your contract specifies the national index, you're being overcharged. Check your contract language.
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05
Duplicate fuel line items
"Fuel surcharge" and "fuel adjustment fee" appearing as separate line items on the same invoice. Rare, but seen on manual billing. Any invoice over $500 is worth scanning line by line.
Suspect an FSC overcharge? The FSC Auditor checks your billed rate against the EIA-indexed standard.
FSC Auditor →How to Audit Your Carrier's FSC for Free
You have three options. Use all three together for any invoice you want to dispute.
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1
Enter your ship date, billed FSC%, and base rate. The tool calculates what your carrier should have charged based on that week's EIA price and flags any discrepancy.
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2
Shows the current EIA diesel price, this week's UPS and FedEx FSC percentages by region, updated every Monday. Bookmark it and check it against your invoices each week.
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3
Carrier tariff documentation
UPS and FedEx both publish their FSC tables publicly. Search "[carrier name] fuel surcharge table [year]" and cross-reference your invoice date against the published rate for that diesel price range.
If your carrier overcharged and you have documentation — ship date, billed FSC%, EIA price for that week — you can file a formal claim. Most carriers resolve FSC disputes within 30 days if the math is clean. Note: dim weight is the parcel equivalent of this cost variable, and your surcharge calculator can model the full accessorial impact of any shipment.