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CII for combination carriers: required CII, rating boundaries and calculator

The carbon intensity a combination carrier must reach each year from 2023 to 2030, by size, with the IMO reference line and the A to E boundaries. Try it on your own ship below.

Updated 2026-10-20

5 combination carriers reported to the EU MRV register for 2025. For a 110,000 dwt combination carrier the required CII is 3.33 in 2026 and 3.23 in 2027; it is still rated C up to 3.53 in 2026 and 3.43 in 2027.

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Required CII for combination carriers, 2023 to 2030

Size20232024202520262027202820292030
50,000 dwt5.815.695.575.445.285.124.964.80
110,000 dwt3.563.483.413.333.233.143.042.94

g CO₂ per dwt-nautical mile. Required CII = (1 − Z/100) × a × capacity−c, with Z from 5% in 2023 to 21.5% in 2030 (resolution MEPC.338(76) as amended).

The reference line

CIIref=a × Capacity−c

Capacity basis: deadweight (G2, resolution MEPC.353(78)).

Rating boundaries in 2026

SizeA up toB up toC up toD up toE
50,000 dwt4.745.235.776.20above
110,000 dwt2.903.203.533.80above

Boundaries are the required CII multiplied by 0.87, 0.96, 1.06, 1.14 (G4, resolution MEPC.354(78)).

Rated D or E?

A ship rated D three years running, or E once, needs a corrective action plan in its SEEMP Part III. How the plan is prepared, or check what EU ETS and FuelEU cost the same ship in the EU ETS and FuelEU calculators.

Questions

What is the required CII for a 110,000 dwt combination carrier in 2027?

3.23 g CO₂ per dwt-nautical mile: the reference value of 3.74 reduced by 13.625%.

Which capacity is used for the CII of a combination carrier?

Deadweight.

What are the CII rating boundaries for combination carriers?

The required CII multiplied by 0.87, 0.96, 1.06 and 1.14. For a 110,000 dwt ship in 2026 a CII up to 2.90 is A, up to 3.20 B, up to 3.53 C, up to 3.80 D, and above that E.

How many combination carriers report to the EU MRV register?

5 in the reporting period 2025, with a median of 3,380 tonnes of CO₂ each.

Check every ship in your fleet

EU ETS, FuelEU, CII and UK ETS for each ship, from the public register or your own data.

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CII for other ship types

Bulk carriersTankersContainer shipsGeneral cargo shipsGas carriersRefrigerated cargo carriersLng carriersRo-ro cargo shipsRo-pax shipsCruise shipsVehicle carriers