Fuel Price Forecasting: How Analysts Predict Petrol and Diesel Prices

Why Forecasting Matters (and Its Limits)

Whether you are a fleet manager hedging diesel costs, a government setting fuel duty rates, or a household budgeting for driving expenses, knowing the direction of fuel prices matters. But fuel prices sit at the end of a long, volatile chain: crude oil markets, refinery capacity, currency movements, taxes, and seasonal demand all contribute. Forecasting means narrowing uncertainty around each link, not eliminating it.

A 2021 IMF study of commodity price forecasting accuracy found that professional crude oil forecasts for horizons beyond 3 months had no significant edge over a simple random walk. The upshot: treat forecasts as scenario tools, not predictions.

Input 1: Crude Oil — The Dominant Driver

Crude oil typically accounts for 50–60% of retail petrol cost in a market-priced country (see our price at the pump breakdown for the full stack). Brent crude is the global benchmark; WTI is the US marker. Most professional forecasters start with a crude outlook and build upward.

The key inputs into a crude forecast:

• OPEC+ production targets — the cartel controls roughly 40% of global supply. Watch the OPEC press releases and compliance data (actual vs. target production).
• Global demand growth — the IEA and EIA publish monthly demand outlooks. Emerging-market demand (China, India) has driven most marginal demand growth since 2010.
• US shale production — the Baker Hughes rig count and EIA weekly production figures give real-time signals on US supply response to price.
• Geopolitical risk premium — conflicts in oil-producing regions add 5–15% risk premiums to crude. These are by definition unpredictable but are reflected in options volatility (OVX index).

Input 2: Crack Spreads — The Refinery Margin

Even when crude is stable, retail prices can spike if refineries are running tight. The "crack spread" is the margin between crude input cost and refined product price. A 3:2:1 crack spread (3 barrels crude → 2 petrol + 1 diesel) is a standard industry measure.

Crack spreads widen when refinery capacity is constrained: hurricanes shutting Gulf Coast refineries (Hurricane Harvey 2017 spiked US crack spreads 70% in a week), seasonal maintenance windows, or years of underinvestment in refining capacity. They compress when crude demand falls or refinery output increases. The NYMEX RBOB/Brent crack is a real-time indicator tracked on commodity platforms.

Input 3: Currency — The Exchange Rate Amplifier

Crude is priced in US dollars globally. For any country not using USD, the domestic fuel price = (crude price × exchange rate) + refining margin + taxes. A country whose currency depreciates against the dollar sees pump prices rise even if crude is flat.

This effect is pronounced in emerging markets. In 2022, the South African rand, Turkish lira, and Pakistani rupee all depreciated sharply against the dollar, adding 20–40% to local fuel costs on top of the crude spike — a double burden. To see how currency affects the prices you're comparing internationally, the compare prices guide explains our normalisation methodology.

Input 4: Taxes — The Floor

In most European countries, 50–60% of retail petrol is tax (excise + VAT). This creates a price floor: even if crude falls to zero, consumers still pay the tax component. Governments can cut fuel taxes to provide relief — as Germany, France, and the UK all did in 2022 — but this is temporary and politically difficult to reverse. Read about the EU fuel tax harmonisation debate for the policy backdrop.

Input 5: Seasonal Demand

Petrol demand follows the northern hemisphere driving season (peak: June–August). Diesel demand peaks in winter (heating oil is chemically similar). Refineries switch product output mix between seasons. Forecasters add a seasonal adjustment — typically ±3–8% on retail prices depending on the market.

Putting It Together: A Simple Scenario Framework

Analysts often build three scenarios — bull (high price), base, and bear (low price) — by varying key inputs. For example, a 12-month forecast framework might vary:

• Brent crude: $70 (bear) / $85 (base) / $105 (bull)
• Crack spread: compressed / normal / wide
• Local currency: stable / –5% depreciation / –15% depreciation
• Tax changes: none / –2p/L temporary cut / +2p/L increase

The combination of these inputs gives a plausible range for domestic retail prices. The range is typically wider than people expect — 30–40% between bear and bull is not unusual over a 12-month horizon.