Since January 2026, shipping pays full price under the EU Emissions Trading System: 100% of in-scope emissions need allowances, and the scheme now counts methane (CH₄) and nitrous oxide (N₂O) alongside CO₂. On a typical deep-sea voyage touching Europe, that is a five-to-six-figure euro line item — large enough to flip which routing wins, and large enough that getting it wrong in a voyage estimate costs real money. This guide walks through exactly how the number is built, with a worked example you can reproduce.
- The EU ETS covers ships of 5,000 GT and above calling at EU/EEA ports: 100% of emissions between two EU ports, 50% of emissions on voyages into or out of the EU, and 100% of at-berth emissions in EU ports.
- The phase-in is over: 40% of emissions needed allowances in 2024, 70% in 2025, and 100% from 2026 onward.
- From 2026 the scheme covers CO₂, CH₄, and N₂O — expressed together as CO₂-equivalent.
- Allowance (EUA) prices float with the carbon market; voyage estimates typically price them in the €60–90/tonne range.
- A single Rotterdam–Singapore supramax voyage produces roughly 1,300 in-scope EUAs — about €96,000 at €75/EUA.
#The scope rules that decide everything
The cost calculation starts with geography, not fuel. The regulation assigns a scope percentage to each voyage based on its ports: a voyage between two EU or EEA ports is 100% in scope; a voyage from an EU port to a non-EU port (or the reverse) is 50% in scope; a voyage touching no EU port is out of scope entirely. On top of that, all emissions while at berth in an EU port count at 100%, whatever the voyage pattern around them.
This is why the ETS line in an estimate cannot be a flat percentage of bunkers. Rotterdam to Hamburg and Rotterdam to Singapore burn very different fuel over very different scope fractions. The route itself — which legs are sailed, which ports are EU — is the first input, which is why serious calculators compute the actual sea route before applying any emission factor.
#From fuel to allowances, step by step
- 1Compute the voyage: distance over real sea lanes, days at sea at the planned speed, days in port.
- 2Fuel burned = days at sea × daily consumption, plus port days × port consumption.
- 3Emissions = fuel × the MRV default factor for that fuel (VLSFO: 3.151 tCO₂ per tonne of fuel; CH₄ and N₂O are added with their default factors and converted to CO₂e using GWP values).
- 4Apply the geographic scope: 100% / 50% / 0% for the voyage legs, 100% for EU at-berth emissions.
- 5Apply the phase-in for the compliance year — 100% from 2026.
- 6Multiply the resulting tonnes of CO₂e by your EUA price assumption. That is the euro line for the estimate.
#A worked example: Rotterdam to Singapore
Take a supramax bulker, 12.5 knots, burning 28 t/day of VLSFO at sea, 4 port days at 4 t/day, about 8,440 nautical miles via Suez. That is roughly 28 days at sea and 788 tonnes of fuel underway plus 16 tonnes in port — 804 tonnes total.
Run the same ship Rotterdam to Barcelona and the scope jumps to 100% while the fuel drops — the ETS line can end up a larger share of a short intra-EU voyage than of a deep-sea one. And because the Cape of Good Hope routing burns far more fuel than Suez, the ETS line also changes the Suez-vs-Cape comparison: carbon now sits alongside bunkers, days, and canal tolls in the routing decision.
You can reproduce this exact calculation — your ports, your consumption, your EUA price — with the free EU ETS calculator at /tools/eu-ets-calculator. It routes over real sea lanes and applies the scope and phase-in rules automatically.
#What changed in 2026 specifically
- Phase-in complete: allowances now cover 100% of in-scope emissions (2024: 40%, 2025: 70%).
- Methane and nitrous oxide joined CO₂ in the scheme. For conventional fuels the CO₂e uplift is modest (around 1.5%); for LNG with methane slip it is material.
- Verified 2025 emissions had to be covered by allowances surrendered in 2026 — the first year most operators felt the full invoice.
#Who carries the cost
The compliance obligation sits with the shipping company — the DOC holder surrenders the allowances. But commercially the cost moves: standard time-charter clauses (including the widely adopted BIMCO ETS clauses) pass allowance costs to the time charterer, on the logic that the charterer controls routing, speed, and therefore emissions. Under voyage charters, owners price the ETS into freight. Either way, the party doing the voyage estimate needs the number before fixing — we cover the allocation question in detail in a companion piece on who pays the EU ETS.
#Getting the number into your estimates
Doing this by hand means maintaining MRV factor tables, an EU/EEA port list, the phase-in schedule, and the gas coverage rules — all of which change on January 1 more often than not. The alternative is one API call: the Marine OS Voyage Emissions API takes ports, speed, consumption, and fuel, and returns emissions by gas, EUAs due, euro cost at your EUA price, FuelEU Maritime exposure, and an indicative CII rating, with every assumption echoed back and overridable.
Put the carbon line in every estimate
One GET request returns the route, the emissions, the EUAs due, and the euro cost — before you fix. Free 100-call trial key by email.
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