The bunker adjustment factor, or BAF, is a floating surcharge that passes changes in ship fuel prices through to freight rates. Carriers publish BAF per trade lane and container type, usually reviewed monthly or quarterly against a fuel price index, so base rates can stay stable while fuel moves.
Bunker fuel is one of the largest costs of running a vessel, and its price is volatile. Rather than reprice freight constantly, carriers split the rate into a base plus BAF, adjusting the surcharge mechanically from published fuel indices and each trade’s average consumption.
Fuel-related surcharges gained a second layer when low-sulphur fuel rules took effect in 2020; many carriers introduced low-sulphur or environmental fuel fees alongside or inside BAF. Names differ by carrier, but the logic is the same: a formula-driven fuel pass-through separate from the base rate.
BAF is commercial, but fuel economics shape operations you can see in tracking: slower sailing speeds to burn less, routing choices, and schedule padding. If a lane’s transit times lengthen across carriers in TrackingMCP, fuel strategy is a common cause, and the ETA fields on tracked shipments absorb those choices.
The bunker adjustment factor, or BAF, is a floating surcharge that passes changes in ship fuel prices through to freight rates. Carriers publish BAF per trade lane and container type, usually reviewed monthly or quarterly against a fuel price index, so base rates can stay stable while fuel moves.
Each carrier publishes its own formula, typically a fuel price index averaged over a reference period, multiplied by an assumed fuel consumption per container for the trade. The result is a per-container amount reviewed on a fixed cycle.
Contracts can fix it, cap it, or float it with the published formula. Many shippers accept a floating BAF in exchange for a stable base rate; large tenders sometimes negotiate all-in rates that absorb it.
Track transit times by carrier →
Carrier data health →
More in Charges & free time: Demurrage · Detention · Demurrage & detention · Demurrage vs detention vs storage · Free time · Last free day (LFD) · Per diem · Terminal handling charge (THC) · General rate increase (GRI) · Peak season surcharge (PSS) · Currency adjustment factor (CAF) · War risk surcharge (WRS) · Browse all 106 terms →