Tanker freight rates — how shipping costs move from crude benchmarks to pump prices

The Worldscale system

Tanker freight for crude oil is priced using the Worldscale system, jointly administered by the Worldscale Association (London) and its New York counterpart. Each year, the Association publishes a flat rate (WS 100) for every major tanker route, calculated to represent the cost of operating a standard vessel at a defined speed on that route, earning a fixed daily hire.

Market rates are then quoted as a percentage of WS 100. In a balanced market, VLCC routes from the Middle East Gulf to Japan or the US Gulf might trade at WS 60–80 (below the flat rate, reflecting fleet oversupply). During the 2022 rate spike, Suezmax rates on the Black Sea–Mediterranean route hit WS 400–500 as Russian crude suddenly needed alternative destinations and ships were scrambling for position.

The Baltic Exchange and S&P Global Platts publish daily freight rate assessments for all major routes. Clarksons Research provides the most comprehensive historical tanker database used by analysts and traders.

Baltic Dirty Tanker Index

The Baltic Dirty Tanker Index (BDTI) aggregates freight rates for crude oil tankers across 11 benchmark routes into a single composite index. It is published each business day by the Baltic Exchange and is the industry's standard headline measure of tanker market conditions.

For refined product shipping (petrol, diesel, jet fuel), the equivalent index is the Baltic Clean Tanker Index (BCTI), which covers product tanker routes. The BCTI is particularly relevant to understanding fuel import costs for countries like West Africa, Southeast Asia, and smaller island economies that import refined products rather than crude. See our West Africa refinery capacity article for how product tanker costs compound the region's fuel pricing challenge.

Fleet types and route economics

Tanker economics are driven by vessel size. Larger vessels carry more barrels per trip and have lower per-barrel freight costs, but are limited to deep-water terminals and cannot transit the Suez Canal above a certain draught. Key size classes:

• VLCC (Very Large Crude Carrier): 200,000–320,000 dwt, 2 million+ barrels per load. The dominant vessel for long-haul crude (Middle East to Asia, West Africa to Asia). Very low USD/barrel cost when rates are moderate. Cannot transit Suez fully laden.
• Suezmax: 120,000–200,000 dwt. The largest vessel that can transit the Suez Canal fully laden. Key route: Black Sea/Mediterranean to NW Europe and Asia.
• Aframax: 80,000–120,000 dwt. Flexible, can call at more ports. Dominant for North Sea, Baltic, Caribbean, and intra-Asian trades.
• MR (Medium Range) tanker: 25,000–55,000 dwt. Used primarily for refined product shipping (clean tanker trade).

The EIA's maritime crude oil and petroleum product transport data tracks US import freight costs. The UNCTAD Review of Maritime Transport publishes an annual comprehensive overview of global tanker fleet capacity and utilisation.

The Russia rerouting effect

The most significant tanker market disruption in recent history was triggered by Western sanctions on Russian crude after the February 2022 invasion of Ukraine. Prior to the invasion, Russia exported approximately 3.5 mb/d of crude oil, mostly on short-haul Aframax voyages to European refineries (Baltic to NW Europe, Black Sea to Mediterranean). Post-sanctions, this crude was redirected to India and China — voyages five to seven times as long.

The voyage-length multiplication had a dramatic effect on effective fleet availability. A tanker making one round trip from the Baltic to Rotterdam in the time it takes to make one trip to India is, in effect, using four to five times as many tonne-days per barrel delivered. The global tanker fleet did not grow by 4–5x, so effective supply tightened sharply. By late 2022, Aframax rates on Baltic routes were five times their 2021 average.

Europe simultaneously needed to source crude from further away — the US Gulf, West Africa, Middle East — adding VLCC and Suezmax demand at the same time. The IEA Oil Market Reports from 2022 tracked these flow changes in detail. See our Russia–Ukraine fuel prices article for the broader market impact.

How freight feeds into pump prices

Freight costs enter the pump price through the import parity price calculation. For a country importing crude or refined products, the delivered cost equals the FOB price at the load port plus freight. A doubling of Aframax rates from WS 80 to WS 160 on a Black Sea–Mediterranean route might add USD 3–4/bbl to the CIF cost of crude for a Mediterranean refinery — which translates into roughly USD 0.02–0.03/litre on the pump price of petrol or diesel.

For product tankers (refined fuel imports), the pass-through is even more direct: the retail price of imported petrol or diesel moves by roughly USD 0.01/litre per USD 1/bbl change in product tanker freight cost. In countries with formula-based pricing — South Africa, India, Ghana — freight rate changes are explicitly built into the monthly price formula, making the pass-through both transparent and rapid. See our refinery gate price entry for the full pump price build-up.

Live crude price data — which reflects freight conditions in the benchmarks — is available in the FuelTheGuide Explorer. For the complete structural picture of what drives prices at the pump, see our guide to what makes up the price at the pump.