Towage fuel surcharges rose sharply in 2026. In Houston, the towage fuel surcharge reached 3.4 times its 2025 level on a like-for-like call. It now makes up about a quarter of the towage bill, up from about 6% in 2025.
To see whether Houston was an isolated case, we looked at a sample of other major ports. The pattern held. In Rotterdam, Antwerp and Singapore, the towage fuel surcharge’s share of the towage bill roughly doubled or more after the start of 2026.
A voyage estimate may look attractive until a cost assumption turns out to be out of date. If your towage allowance is based on 2025 invoices, it could be missing a large part of the cost. Here’s what we’re seeing, along with the questions worth asking before you fix.
How much have towage fuel surcharges risen in 2026?
Before 2026, towage fuel surcharges were a modest line item, typically 4–11% of the towage bill. In Houston, the surcharge reached about a quarter of the bill in Q3 2026.
The table gives the same comparison in numbers.
Port | Surcharge share of towage bill, 2025 | Surcharge share of towage bill, Q3 2026 |
|---|---|---|
Houston | About 6% | 26% |
Rotterdam | About 9% | 19% |
Singapore | About 8% | 17% |
Antwerp | About 4% | 15% |
Houston towage fuel surcharge: 3.4 times 2025 levels
Houston is where the change stands out most clearly. In our analysis, the towage fuel surcharge held steady through 2025, then jumped in March 2026 and has stayed high since.
Comparing like-for-like calls in April–September of each year, our analysis puts the surcharge at 3.4 times its 2025 level. The underlying towage cost per call changed little over the same period, which suggests most of the 2026 increase in Houston towage has come through the surcharge line.
In practice, an estimate built on the 2025 surcharge level could come in roughly a fifth short. With the underlying towage cost broadly unchanged, a surcharge share that moves from about 6% to about a quarter lifts the total towage bill by roughly a quarter, so a 2025-based allowance covers about four fifths of it.
Why towage fuel surcharges jumped in March 2026
The jump coincides with the start of the conflict with Iran at the end of February 2026 and the rise in fuel prices that followed. Fuel surcharges are designed to pass changes in fuel costs on to customers, so timing like this is what you’d expect to see. We won’t try to forecast where fuel prices go next.
What to check before fixing: three questions
Take a Houston port call. The towage allowance is entered, the voyage economics are reviewed and the fixture moves forward. Later, the final invoice includes a fuel surcharge calculated differently from what the estimator assumed.
A useful port estimate needs the context behind the number. Historical data helps establish a reference; context helps you judge whether that reference applies to the voyage being negotiated.
Was the surcharge included? Was it based on a negotiated contract? A headline towage allowance can conceal those distinctions.
Check whether historical costs include fuel surcharges, so you're not comparing an inclusive actual cost with an incomplete estimate.
Check how the fuel surcharge interacts with your negotiated discount. The calculation base can materially affect the total towage cost.
Confirm the terms, or carry an explicit allowance
How the calculation base changes the towage estimate
Consider a hypothetical call with $20,000 in towage charges before a 30% discount and an assumed 20% fuel surcharge. The applicable calculation changes the estimate by $1,200.
Calculation base | Amount the surcharge applies to | Fuel surcharge at 20% |
|---|---|---|
Before discount | $20,000 | $4,000 |
After 30% discount | $14,000 | $2,800 |
Difference | $1,200 |
In 2026, that difference matters more. In Houston, the towage fuel surcharge’s share of the towage bill has risen from about 6% in 2025 to about a quarter in Q3 2026.
This is where PortLog can help bring critical questions forward, while the chartering team still has time to clarify assumptions and price the voyage accordingly: placing these checks alongside the estimate, together with the tug numbers, movements and service scope of comparable calls.
Before the fixture is agreed, the team should be able to see both the expected port cost and the assumptions that could change it.
About the data: how we analysed towage fuel surcharges
Figures come from Marcura's analysis of port call costs, in US dollars, from January 2023 to September 2026. The comparison ports are a sample chosen to test whether Houston was an isolated case, not a survey of every port. The Houston year-on-year comparison is like-for-like, so it isn't skewed by changes in which ships call; other figures cover all calls. Surcharges are counted only where billed as a separate line, and Q3 2026 data is still incomplete.
Janani Yagnamurthy
SVP, Product, Strategic Growth
