2021 Honda Clarity — Full Specifications
As an Amazon Associate and CJ Affiliate and AWIN publisher we earn from qualifying purchases. Links below are affiliate links.
Running gear matters most — before anything else, UK: check tyre prices at TirendoUS: check wheel & tyre prices at WheelHero for this car's fitment.
The 2021 Honda Clarity is a saloon/sedan powered by a 1.5L 4-cyl regular gasoline engine. It returns around 50 mpg (UK) / 42 mpg (US EPA) combined. Owners often keep a Honda Clarity workshop manual to hand for servicing and repairs.
Compared with the 2020 Honda Clarity: Fuel economy is essentially unchanged at around 50 mpg (UK) combined. The engine line-up listed by EPA is unchanged.
Full Specifications
| Engine | 1.5L 4-cyl |
|---|---|
| Transmission | Automatic (variable gear ratios) |
| Fuel Type | Regular Gasoline |
| Powertrain | Plug-in Hybrid |
| Drive | Front-Wheel Drive |
| Body Style | Saloon/Sedan |
| Passenger Volume (EPA) | 102 cu ft (2,888 L) |
| Luggage Volume (EPA) | 16 cu ft (453 L) |
| Fuel Economy (UK) | 50 combined / 53 urban / 48 extra-urban mpg |
| Fuel Economy (US EPA) | 42 combined / 44 city / 40 highway mpg |
| CO₂ Emissions | 35 g/km |
| EPA Greenhouse Gas Score | 10 / 10 (10 = lowest emissions) |
| EPA Est. Annual Fuel Cost | $1,600 (15,000 mi/yr, US prices) |
Engine & Transmission Options
EPA lists 1 configuration for the 2021 Honda Clarity, all with the 1.5L 4-cyl engine. 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 |
|---|---|---|---|---|---|---|
| 1.5L 4-cyl (Plug-in Hybrid) | Automatic (variable gear ratios) | Front-Wheel Drive | 50 | 42 (44/40) | 35 | $1,600 |
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 102 cubic feet (about 2,888 litres) and luggage volume at 16 cubic feet (about 453 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 Honda Clarity
Running Costs: 2021 Honda Clarity
Covering around 8,000 miles a year in a 2021 Honda Clarity at 50 mpg combined, expect roughly 727 litres of fuel annually — multiply by your local price per litre for a cost estimate. For US owners, the EPA estimates about $1,600 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 Honda Clarity Safety Ratings (NHTSA)
No NHTSA crash-test rating is on record for this model year. The NHTSA rates only a subset of vehicles each year; you can browse every rated vehicle on our NHTSA Safety Ratings hub.
Recalls & Owner Complaints (NHTSA)
NHTSA lists no safety recall campaigns for the 2021 Honda Clarity as of 6 October 2026. Recalls can be issued years after a model is sold, so it is still worth checking your own VIN.
Owners have filed 4 complaints with NHTSA about the 2021 Honda Clarity. The most-reported areas are Forward collision avoidance (1), Steering (1), Electrical system (1). Complaints include 1 reported crash. That is well below the median of 10 complaints across the 5 Honda Clarity model years in our data.
Used-buyer checklist for the 2021 Honda Clarity
Based on where NHTSA recalls and owner complaints cluster for this model year, these are the areas worth checking before you buy:
- Driver-assist sensors (1 owner complaint) — Check that driver-assist warning lights are off and sensors are clean and undamaged.
- Steering (1 owner complaint) — Check for play, noise or heavy steering, and ask whether any steering recall work was done.
- Electrical system (1 owner complaint) — Test every switch, window, light and warning lamp on a test drive, and ask about battery or alternator replacements.
- Throttle & cruise control (1 owner complaint) — Check throttle response and cruise control are smooth, and ask about any software or throttle recalls.
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
Honda models in our database average about 35 mpg (UK) combined on their most efficient configuration; the 2021 Honda Clarity's 50 mpg is 15 mpg above that make average. Its 35 g/km CO₂ figure is 162 g/km lower than the 197 g/km Honda average.
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 Honda Clarity
Frequently Asked Questions
What engine does the 2021 Honda Clarity have?
It's fitted with a 1.5L 4-cyl regular gasoline engine, paired with a automatic (variable gear ratios) transmission.
What is the fuel economy of the 2021 Honda Clarity?
The most efficient configuration returns around 50 mpg (UK) combined, or 42 mpg on the US EPA cycle.
How much does the 2021 Honda Clarity cost to fuel per year?
The US EPA estimates about $1,600 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 Honda Clarity have any recalls?
NHTSA lists no safety recall campaigns for the 2021 Honda Clarity as of 6 October 2026. Recalls can be issued years after a model is sold, so it is still worth checking your own VIN.
What are the most common problems reported for the 2021 Honda Clarity?
Among the 4 owner complaints filed with NHTSA, the most-reported areas are Forward collision avoidance (1 complaint), Steering (1 complaint), Electrical system (1 complaint). 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 Honda Clarity have?
EPA measures interior passenger volume at 102 cubic feet (about 2,888 litres) and luggage volume at 16 cubic feet (about 453 litres). These are US EPA interior-volume figures, which are measured differently from the UK boot-capacity numbers manufacturers quote.