2021 Subaru Legacy — Full Specifications
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The 2021 Subaru Legacy is a saloon/sedan offered with 2 engines (2.4L 4-cyl turbo, 2.5L 4-cyl). Its most fuel-efficient configuration returns around 36 mpg (UK) / 30 mpg (US EPA) combined, with 32–36 mpg (UK) across all configurations. Owners often keep a Subaru Legacy workshop manual to hand for servicing and repairs.
Compared with the 2020 Subaru Legacy: Fuel economy is essentially unchanged at around 36 mpg (UK) combined. The engine line-up listed by EPA is unchanged. It carries the same 5★ overall NHTSA rating. EPA passenger volume changes from 105 to 106 cu ft.
Full Specifications
| Engine (most efficient) | 2.5L 4-cyl |
|---|---|
| Engine options | 2.4L 4-cyl turbo · 2.5L 4-cyl |
| Transmission (most efficient) | Automatic (AV-S8) |
| Fuel Type | Regular Gasoline |
| Powertrain | Conventional |
| Drive | All-Wheel Drive |
| Body Style | Saloon/Sedan |
| Passenger Volume (EPA) | 106 cu ft (3,002 L) |
| Luggage Volume (EPA) | 15 cu ft (425 L) |
| Fuel Economy (UK) | 36 combined / 32 urban / 42 extra-urban mpg |
| Fuel Economy (US EPA) | 30 combined / 27 city / 35 highway mpg |
| CO₂ Emissions | 183 g/km |
| EPA Greenhouse Gas Score | 6 / 10 (10 = lowest emissions) |
| EPA Est. Annual Fuel Cost | $2,250 (15,000 mi/yr, US prices) |
Engine & Transmission Options
EPA lists 2 configurations for the 2021 Subaru Legacy across 2 engines (2.4L 4-cyl turbo, 2.5L 4-cyl). Combined fuel economy ranges from 27 to 30 mpg (US), or 32 to 36 mpg (UK), depending on engine, transmission and drive. The headline figures at the top of this page describe the most fuel-efficient configuration.
| Engine | Transmission | Drive | MPG (UK) | MPG (US) | CO₂ g/km | Fuel cost / yr |
|---|---|---|---|---|---|---|
| 2.4L 4-cyl turbo | Automatic (AV-S8) | All-Wheel Drive | 32 | 27 (24/32) | 205 | $2,500 |
| 2.5L 4-cyl | Automatic (AV-S8) | All-Wheel Drive | 36 | 30 (27/35) | 183 | $2,250 |
MPG (US) shows combined, with city/highway in brackets. Highlighted row = the configuration used for the headline figures. Source: US EPA fueleconomy.gov.
EPA measures interior passenger volume at 106 cubic feet (about 3,002 litres) and luggage volume at 15 cubic feet (about 425 litres). These are US EPA interior-volume figures; they are measured differently from the boot capacity numbers UK manufacturers quote.
Owner Essentials for the 2021 Subaru Legacy
Running Costs: 2021 Subaru Legacy
Covering around 8,000 miles a year in a 2021 Subaru Legacy at 36 mpg combined, expect roughly 1,010 litres of fuel annually — multiply by your local price per litre for a cost estimate. For US owners, the EPA estimates about $2,250 a year in fuel for the most efficient configuration (15,000 miles, national average prices). Work out exact fuel costs with the fuel cost calculator on 247Calculators.
Convert between MPG and L/100km with the unit converters on 247QuickTools. Not sure what tyre size fits? 247TyreCheck explains tyre sizing.
Only need this car occasionally? See our buy vs rent comparison.
2021 Subaru Legacy Safety Ratings (NHTSA)
Recalls & Owner Complaints (NHTSA)
NHTSA lists 3 safety recall campaigns that include the 2021 Subaru Legacy (as of 6 October 2026). Most affected areas: Power train (2), Air bags (1). A campaign often covers several model years or models, so check your own VIN to see whether your car is affected.
- Air bags — campaign 24V227000, reported 22 March 2024. Risk: An air bag that does not deploy during a crash can increase the risk of injury.
- Power train — campaign 23V755000, reported 9 November 2023. Risk: An inoperative inhibitor switch may prevent the reverse lights from illuminating and the rearview camera image from displaying, increasing the risk of a crash.
- Power train — campaign 22V485000, reported 8 July 2022. Risk: An improperly secured drive chain may slip and break, causing a loss of drive power and increasing the risk of a crash.
Owners have filed 31 complaints with NHTSA about the 2021 Subaru Legacy. The most-reported areas are Unspecified (7), Air bags (6), Electrical system (5). Complaints include 1 reported injury. That is well below the median of 104 complaints across the 16 Subaru Legacy model years in our data.
Used-buyer checklist for the 2021 Subaru Legacy
Based on where NHTSA recalls and owner complaints cluster for this model year, these are the areas worth checking before you buy:
- Transmission & drivetrain (2 recall campaigns) — On the test drive, watch for hesitation, jerking or slipping between gears and ask for transmission service history.
- Air bags (1 recall campaign · 6 owner complaints) — Confirm any air bag inflator or module recalls were completed — enter the VIN at nhtsa.gov/recalls.
- Electrical system (5 owner complaints) — Test every switch, window, light and warning lamp on a test drive, and ask about battery or alternator replacements.
- Visibility (5 owner complaints) — Check wipers, washers and demisters work properly.
Source: US NHTSA recall and consumer-complaint databases, retrieved 6 October 2026. Complaints are unverified owner reports, not confirmed defects. Check any vehicle by VIN at nhtsa.gov/recalls, and see our guide to checking a used car for recalls.
How It Compares
Subaru models in our database average about 33 mpg (UK) combined on their most efficient configuration; the 2021 Subaru Legacy's 36 mpg is 3 mpg above that make average. Its 183 g/km CO₂ figure is 23 g/km lower than the 206 g/km Subaru average.
Of the 16 Subaru Legacy model years we cover, the 2021 is the most economical on its best configuration (36 mpg UK combined). See every Subaru Legacy year side by side.
Last updated: · Data: US EPA (fueleconomy.gov) and NHTSA safety ratings 18 July 2026; NHTSA recalls and complaints 6 October 2026; Wikidata & curated EU catalogue 18 July 2026; European generation and engine data from Wikipedia 7 October 2026
Vehicle data sourced from manufacturer specifications. Always verify with your vehicle handbook or a qualified mechanic. This is a reference tool, not professional advice.
Recommended Accessories for the 2021 Subaru Legacy
Frequently Asked Questions
What engine does the 2021 Subaru Legacy have?
EPA lists 2 engines for the 2021 Subaru Legacy: 2.4L 4-cyl turbo, 2.5L 4-cyl. The most fuel-efficient configuration pairs the 2.5L 4-cyl with a automatic (av-s8).
What is the fuel economy of the 2021 Subaru Legacy?
The most efficient configuration returns around 36 mpg (UK) combined, or 30 mpg on the US EPA cycle. Across all configurations the UK combined figure runs from 32 to 36 mpg.
How much does the 2021 Subaru Legacy cost to fuel per year?
The US EPA estimates about $2,250 a year in fuel for the most efficient configuration, based on 15,000 miles of mixed driving and national average fuel prices. Your own cost will depend on mileage and local prices.
Does the 2021 Subaru Legacy have a good safety rating?
It holds an overall NHTSA rating of 5 stars, with 5 stars for frontal crash protection.
Does the 2021 Subaru Legacy have any recalls?
NHTSA lists 3 safety recall campaigns that include the 2021 Subaru Legacy (as of 6 October 2026). Most affected areas: Power train (2), Air bags (1). A campaign often covers several model years or models, so check your own VIN to see whether your car is affected.
What are the most common problems reported for the 2021 Subaru Legacy?
Among the 31 owner complaints filed with NHTSA, the most-reported areas are Unspecified (7 complaints), Air bags (6 complaints), Electrical system (5 complaints). Complaints are unverified owner reports, not confirmed defects, and raw counts rise with how many cars were sold.
How much interior and luggage space does the 2021 Subaru Legacy have?
EPA measures interior passenger volume at 106 cubic feet (about 3,002 litres) and luggage volume at 15 cubic feet (about 425 litres). These are US EPA interior-volume figures, which are measured differently from the UK boot-capacity numbers manufacturers quote.