Litres to Gallons Converter UK

Last verified: • Updated for 2026/26 tax year

Convert between litres and UK imperial gallons instantly. Essential for British drivers calculating fuel costs, comparing tank sizes, and understanding fuel economy figures. 1 UK gallon = 4.546 litres (20% larger than US gallon).

Quick Convert (Litres to UK Gallons)

Litres to UK Gallons

0.00
UK gallons (imperial)
0.00
US gallons
Also equals:
0.00 UK pints

UK Gallons to Litres

0.00
litres
Also equals:
0 millilitres (ml)

UK vs US Gallon - Critical Difference for British Drivers

UK Imperial Gallon

1 UK gallon = 4.54609 litres

Used in: United Kingdom, Ireland, Canada (some contexts)

Contains: 8 UK pints (568ml each)

Weight of water: 10 pounds (4.536 kg)

Standard for UK MPG figures

US Gallon

1 US gallon = 3.78541 litres

Used in: United States, Latin America

Contains: 8 US pints (473ml each)

Weight of water: 8.34 pounds (3.785 kg)

US MPG will be lower!

Important: The UK gallon is approximately 20% larger than the US gallon. This matters when reading American car reviews, comparing fuel economy figures, or buying products online from American retailers. A car rated at 40 UK MPG only achieves about 33 US MPG!

Batch Conversion - Multiple Values

Enter multiple values separated by commas or spaces to convert them all at once.

Common UK Car Fuel Tank Sizes

Reference for British drivers - typical tank capacities for popular UK vehicles:

Small Cars

Ford Fiesta, Vauxhall Corsa, VW Polo, Toyota Yaris

40-45L
8.8-9.9 UK gallons

Medium Cars

VW Golf, Ford Focus, Vauxhall Astra, Honda Civic

50-55L
11-12.1 UK gallons

Large Saloons

BMW 3 Series, Audi A4, Mercedes C-Class

59-66L
13-14.5 UK gallons

SUVs & 4x4s

Nissan Qashqai, VW Tiguan, Range Rover

60-85L
13.2-18.7 UK gallons

UK Fuel Cost Calculator

Calculate how much it costs to fill your tank at current UK fuel prices:

£71.00
to fill 50 litres (11 UK gallons)

Current UK Fuel Prices (December 2025)

Unleaded Petrol
~142p/L
£6.45 per UK gallon
Diesel
~148p/L
£6.73 per UK gallon
Super Unleaded
~156p/L
£7.09 per UK gallon

Where to Find Cheapest Fuel in the UK

TypeTypical PriceExamples
Supermarkets (Cheapest)138-142p/LAsda, Sainsbury's, Tesco, Morrisons
Independent Stations140-148p/LJet, Texaco, Gulf
Major Brands145-152p/LBP, Shell, Esso
Motorway Services (Most Expensive)155-170p/LWelcome Break, Moto, Roadchef
Money-Saving Tip: Use apps like PetrolPrices.com or Waze to find the cheapest fuel near you. Supermarket forecourts are typically 5-10p per litre cheaper than branded stations, saving around £5 per fill-up on a 50L tank.

Journey Fuel Cost Estimator

£14.34
for 100 miles at 45 MPG

MPG to L/100km Converter

Convert between UK miles per gallon (MPG) and European litres per 100 kilometres:

Enter a value to convert
UK MPG L/100km

Fuel Economy Comparison: UK MPG vs L/100km vs US MPG

UK MPGL/100kmUS MPGEfficiency Rating
25 mpg11.3 L/100km21 mpgPoor (large SUVs, older vehicles)
30 mpg9.4 L/100km25 mpgBelow average (SUVs, performance cars)
35 mpg8.1 L/100km29 mpgAverage (larger petrol cars)
40 mpg7.1 L/100km33 mpgGood (modern petrol cars)
45 mpg6.3 L/100km38 mpgVery good (efficient petrol)
50 mpg5.6 L/100km42 mpgExcellent (diesel, mild hybrid)
55 mpg5.1 L/100km46 mpgOutstanding (efficient diesel)
60 mpg4.7 L/100km50 mpgExceptional (full hybrid)
70 mpg4.0 L/100km58 mpgBest-in-class (hybrids)
100+ mpg2.8 L/100km83 mpgPHEV (plug-in hybrid)
UK vs US MPG Warning: UK MPG figures are always about 20% higher than US MPG because UK gallons are larger. When reading American car reviews or YouTube videos, remember that their MPG numbers will seem lower. A car rated at 40 UK MPG is approximately 33 US MPG.

MPG Conversion Formulas

UK MPG to L/100km

L/100km = 282.481 ÷ UK MPG

Example: Convert 45 UK MPG to L/100km
282.481 ÷ 45 = 6.28 L/100km

L/100km to UK MPG

UK MPG = 282.481 ÷ L/100km

Example: Convert 7.0 L/100km to UK MPG
282.481 ÷ 7.0 = 40.35 UK MPG

UK MPG to US MPG

US MPG = UK MPG × 0.8327

Example: Convert 45 UK MPG to US MPG
45 × 0.8327 = 37.47 US MPG

Litres to UK Gallons Conversion Chart

LitresUK GallonsUS GallonsUK PintsCommon Use
1 litre0.22 UK gal0.26 US gal1.76 pintsMilk carton
2 litres0.44 UK gal0.53 US gal3.52 pintsLarge drink bottle
4.546 litres1 UK gal1.20 US gal8 pints1 UK gallon (exact)
5 litres1.10 UK gal1.32 US gal8.80 pintsJerry can, engine oil
10 litres2.20 UK gal2.64 US gal17.60 pintsSmall fuel top-up
20 litres4.40 UK gal5.28 US gal35.20 pintsFuel can
25 litres5.50 UK gal6.60 US gal44.00 pintsHalf tank (small car)
30 litres6.60 UK gal7.93 US gal52.80 pintsPartial fill
40 litres8.80 UK gal10.57 US gal70.40 pintsSmall car full tank
45 litres9.90 UK gal11.89 US gal79.20 pintsFiesta/Corsa tank
50 litres11.00 UK gal13.21 US gal88.00 pintsGolf/Focus tank
55 litres12.10 UK gal14.53 US gal96.80 pintsMedium car tank
60 litres13.20 UK gal15.85 US gal105.60 pintsLarge saloon tank
70 litres15.40 UK gal18.49 US gal123.20 pintsSUV tank
80 litres17.60 UK gal21.13 US gal140.80 pintsLarge SUV/4x4
100 litres22.00 UK gal26.42 US gal176.00 pintsVan/small lorry

UK Pints, Gallons and Litres

The UK pint is still widely used in British pubs and for milk. Understanding the relationship:

1 UK gallon = 8 UK pints = 4.54609 litres
1 UK pint = 568.26 ml = 0.568 litres
1 litre = 1.76 UK pints = 0.22 UK gallons

UK Pints to Litres Quick Reference

UK PintsLitresmlCommon Example
½ pint0.28 L284 mlHalf pint of beer/lager
1 pint0.57 L568 mlPint of beer, milk bottle
2 pints1.14 L1,137 ml2-pint milk carton
4 pints2.27 L2,273 ml4-pint milk container
6 pints3.41 L3,410 ml6-pint milk container
8 pints4.55 L4,546 ml1 UK gallon
Pub Measure: In UK pubs, draught beer and cider must legally be sold in measures of 1/3 pint, 1/2 pint, or multiples of 1/2 pint. A UK pint (568ml) is notably larger than a US pint (473ml) - about 20% more beer!

Water Storage: Litres and UK Gallons

For water butts, tanks, and gardening calculations:

ContainerLitresUK GallonsWeight (Water)
Small water butt100 L22 gal100 kg
Standard water butt200 L44 gal200 kg
Large water butt350 L77 gal350 kg
IBC tank1000 L220 gal1000 kg
Hot tub (typical)1500 L330 gal1500 kg
Small pool5000 L1100 gal5000 kg
Useful fact: 1 litre of water weighs exactly 1 kg, making calculations easy. 1 UK gallon of water weighs approximately 4.54 kg (10 pounds).

Conversion Formulas

Litres to UK Gallons

UK Gallons = Litres ÷ 4.54609

Example: Convert 50 litres to UK gallons
50 ÷ 4.54609 = 11.00 UK gallons

UK Gallons to Litres

Litres = UK Gallons × 4.54609

Example: Convert 10 UK gallons to litres
10 × 4.54609 = 45.46 litres

Litres to US Gallons

US Gallons = Litres ÷ 3.78541

Example: Convert 50 litres to US gallons
50 ÷ 3.78541 = 13.21 US gallons

Litres to UK Pints

UK Pints = Litres × 1.75975

Example: Convert 5 litres to UK pints
5 × 1.75975 = 8.80 UK pints

Quick Mental Maths Tips

  • Litres to UK gallons: Divide by 4.5 (or multiply by 0.22)
  • UK gallons to litres: Multiply by 4.5
  • Litres to UK pints: Multiply by 1.75 (or divide by 0.57)
  • Remember: 1 UK gallon ≈ 4.5 litres ≈ 8 pints

History: Why Are UK and US Gallons Different?

The difference between UK and US gallons dates back to 1824 when Britain redefined its system of weights and measures.

The British Imperial System (1824)

In 1824, the British Weights and Measures Act established the imperial gallon as the volume of 10 pounds of distilled water at 62°F (17°C). This gave us the UK imperial gallon of 4.54609 litres that we still use today for certain purposes. The system was designed for simplicity: a gallon of water weighs exactly 10 pounds.

The American System

When America declared independence in 1776, it kept using the older English measurements. The US gallon was based on the English wine gallon (also called the Queen Anne gallon), which was defined as 231 cubic inches - equivalent to 3.785 litres. This was already the standard for wine and spirits trade in the American colonies.

Modern UK Usage

Today, the UK officially uses litres for most commercial purposes (including fuel sales since 1995), but imperial gallons and pints are still used for:

  • Draught beer and cider - legally sold in pints
  • Milk - often sold in pints (2-pint, 4-pint cartons)
  • Fuel economy - MPG figures are UK imperial gallons
  • Road distances - miles, not kilometres
  • Speed limits - miles per hour (mph)
Did you know? The UK is one of only three countries (along with Myanmar and Liberia) that hasn't fully adopted the metric system. We use a unique hybrid system - buying petrol in litres but measuring fuel economy in miles per gallon!

Frequently Asked Questions

How many litres are in a UK gallon?

1 UK (imperial) gallon equals exactly 4.54609 litres. This is different from a US gallon which equals only 3.78541 litres. The UK gallon is approximately 20% larger than the US gallon. For quick mental maths, you can use 4.5 litres per UK gallon as a close approximation. This relationship was established by the British Weights and Measures Act of 1824, which defined the gallon as the volume of 10 pounds of water.

What is the difference between UK and US gallons?

A UK imperial gallon is 4.54609 litres, while a US gallon is only 3.78541 litres - making the UK gallon about 20% larger. This difference originated when Britain redefined the gallon in 1824, while America kept the older English wine gallon. This affects fuel economy comparisons significantly: a car rated at 40 UK MPG achieves only about 33 US MPG. Always check which gallon is being referenced when reading American car reviews or fuel economy figures.

How do I convert litres to UK gallons?

To convert litres to UK gallons, divide by 4.54609. For example: 50 litres ÷ 4.54609 = 11 UK gallons. For quick mental maths without a calculator, divide by 4.5 (gives approximately the same result) or multiply by 0.22. Common conversions to remember: 10L = 2.2 gal, 20L = 4.4 gal, 45L = 9.9 gal, 50L = 11 gal.

How many litres is a full tank of petrol in UK cars?

UK car fuel tank sizes vary by vehicle type: Small cars (Ford Fiesta, Vauxhall Corsa, VW Polo) typically have 40-45 litre tanks (8.8-9.9 UK gallons). Medium cars (VW Golf, Ford Focus, Vauxhall Astra) have 50-55 litres (11-12.1 gallons). Large saloons (BMW 3 Series, Audi A4, Mercedes C-Class) have 59-66 litres (13-14.5 gallons). SUVs can have 60-85 litres (13-18.7 gallons). At current 2025 UK prices of around 140-150p per litre, filling a 50L tank costs approximately £70-75.

About This Calculator

JT

James Thompson

BEng (Hons), CEng, IMechE - Automotive Engineer

James is a chartered mechanical engineer with over 15 years of experience in the UK automotive industry. He has worked with major manufacturers including Jaguar Land Rover and Aston Martin, specialising in fuel systems and powertrain efficiency. James contributes to UK Calculator to help British drivers understand fuel consumption, costs, and the quirks of our imperial/metric hybrid measurement system.

Related Calculators

Pro Tips for Accurate Results
  • Double-check your input values before calculating
  • Use the correct unit format (metric or imperial)
  • For complex calculations, break them into smaller steps
  • Bookmark this page for quick future access
Understanding Your Results

Our Litres To Gallons provides:

  • Instant calculations - Results appear immediately
  • Accurate formulas - Based on official UK standards
  • Clear explanations - Understand how results are derived
  • 2025/26 updated - Using current rates and regulations
Common Questions

Is this calculator free?

Yes, all our calculators are 100% free to use with no registration required.

Are the results accurate?

Our calculators use verified formulas and are regularly updated for accuracy.

Can I use this on mobile?

Yes, all calculators are fully responsive and work on any device.

People Also Ask

Yes, our calculators use verified formulas and are regularly updated with current UK rates and regulations. Results are provided for guidance - always consult professionals for major financial decisions.

Absolutely! All our calculators are fully responsive and work perfectly on smartphones, tablets, and desktops. No app download needed.

We update all calculators with new rates as soon as they're announced - typically at the start of each tax year (April) or when significant changes occur.

HMRC Compliant
Secure & Private
4.9/5 Rating
500K+ Users