How to calculate your real weekly UK commute cost

The cheapest commute is not always the one with the lowest pump price. To compare petrol, diesel, electric driving and public transport fairly, calculate the cost of the full return journey: fuel or charging, distance, parking, fares and the number of travel days. Local prices and your vehicle’s real-world efficiency will determine the answer.

Use the full journey cost, not just the pump price

Start with the distance you actually travel. Include both directions, regular diversions and any weekly parking charge. Then record the price you would genuinely pay near your home, workplace or route.

For a petrol or diesel car, use this calculation:

Journey fuel cost = (distance ÷ miles per gallon × 4.546) × price per litre

The 4.546 figure converts imperial gallons into litres. If your car displays litres per 100 kilometres instead, convert the distance to kilometres and use that consumption figure directly.

For an electric vehicle, the basic calculation is:

Charging cost = energy used in kWh × electricity price per kWh

Use the vehicle’s measured consumption where possible. Public rapid charging may cost much more than charging at home, while workplace or overnight tariffs can be different again. Add any parking or connection fees.

Public transport should be calculated from the fare you would actually pay. Check whether a weekly or monthly ticket is cheaper than separate daily tickets, and include any connecting bus, tram or rail journey.

A worked hypothetical comparison

The figures below are illustrative only. They are not a UK average or a current price forecast.

Assume a commuter makes a 36-mile return journey for five days each week. The car uses 42 miles per imperial gallon, petrol costs £1.52 per litre, and parking costs £4 per day.

• Weekly distance: 36 × 5 = 180 miles
• Fuel used: 180 ÷ 42 = 4.29 imperial gallons
• Litres used: 4.29 × 4.546 = about 19.5 litres
• Weekly petrol cost: 19.5 × £1.52 = about £29.64
• Weekly parking: 5 × £4 = £20
• Total weekly driving cost: about £49.64

Now assume an electric car uses 17 kWh per 100 kilometres, the same weekly distance is about 290 kilometres, and home electricity costs 28p per kWh.

• Energy used: 290 ÷ 100 × 17 = about 49.3 kWh
• Home charging cost: 49.3 × £0.28 = about £13.80
• Parking: £20
• Total weekly electric-driving cost: about £33.80

Finally, suppose a weekly public transport ticket costs £42 and requires no separate parking payment. In this example, public transport is cheaper than the petrol car but more expensive than home charging. The result would change if public charging, a different fare, congestion charges or a longer route applied.

Check prices and fares for your actual route

Before deciding, collect prices from the places you would use rather than relying on a national headline figure.

• Compare nearby forecourt prices using a current local price service or retailer app.
• Check the fuel grade your vehicle requires; premium fuel can change the calculation.
• Use your electricity tariff, including time-of-use rates and standing charging fees where relevant.
• Check the charging operator’s live tariff and whether a subscription changes the price.
• Look at the train, bus or tram operator’s fare page for daily, weekly and season-ticket options.
• Confirm workplace, station and town-centre parking charges, including permits and peak-time rates.

A route planner can provide distance and journey time, but it may not include every parking, toll or charging cost. Save the exact route and fare pages you used so you can repeat the comparison when prices change.

What this calculation leaves out

A weekly running-cost comparison is useful, but it is not the full cost of owning or choosing a vehicle. Insurance, servicing, tyres, vehicle tax, depreciation and finance payments may matter when comparing cars over a longer period. Public transport can also involve walking time, missed connections or occasional taxi costs.

Your result may change with traffic, weather, passengers, luggage, driving style and vehicle age. Stop-start urban driving usually produces a different consumption figure from a steady motorway trip. For an electric car, cold weather, motorway speeds and cabin heating can increase energy use.

Run the calculation for a typical week and a difficult week. The cheapest option on paper may not be the most reliable or practical every day. Recheck local fuel, charging, parking and fare prices before making a longer-term decision.

Source: GOV.UK