2021 Mercedes-Benz GLB prices

There are 86 used 2021 Mercedes-Benz GLB cars for sale from UK dealers on AskCar, as of 10 November 2026. Typical asking price £21,500 (the median: half cost less, half cost more). The cheapest is £15,795. The middle half are priced between £19,800 and £23,000. Median mileage: about 47,000 miles.

Dealers lowered the asking price on more than a third of 2021 Mercedes-Benz GLB cars: 39 of the 86 in the 14 days to 10 November 2026.

2021 Mercedes-Benz GLB prices by engine and mileage

A 2021 Mercedes-Benz GLB 2.0 diesel car typically costs £23,000, against £21,000 for the 1.3 petrol, as of 10 November 2026.

EngineAll mileagesUnder 20,000 miles20,000 to 40,000 miles40,000 to 60,000 miles60,000 miles or more
1.3 petrol£21,000Too few for sale£22,000Too few for saleToo few for sale
2.0 diesel£23,000Too few for saleToo few for saleToo few for saleToo few for sale

Only 1 of the 2021 Mercedes-Benz GLB cars for sale have the 1.9 diesel engine, too few to give a typical asking price.

2021 Mercedes-Benz GLB prices by trim

TrimTypical asking price, 2021 cars
AMG Line£20,000
AMG Line Premium£22,000
AMG Line Premium PlusToo few for sale

Only 16 of the 2021 Mercedes-Benz GLB cars for sale are AMG Line Premium Plus, too few to give a typical asking price.

Typical asking prices are of 2021 Mercedes-Benz GLB cars for sale on 10 November 2026, and are given only where at least 20 cars with a price are for sale.

2021 Mercedes-Benz GLB against other years

A 2020 Mercedes-Benz GLB car has a typical asking price of £21,000 and a 2022 one £22,500, as of 10 November 2026.

AskCar lists 841 used Mercedes-Benz GLB across the UK, from 391 dealerships.

As of 10 November 2026, AskCar lists 591,054 cars and vans from 12,888 UK dealerships, read daily from dealer websites: over 99% of UK dealer used car adverts. No dealer pays to be listed.

2021 Mercedes-Benz GLB cars for sale now, page 1 of 2

This page picks out up to 10 cars in each of these groups: best value, cheapest, lowest mileage, recently reduced and newly advertised. A car in more than one group is listed in full once. The groups pick only from cars with photos and an AskCar estimate, priced at £500 or more and no more than 25% under that estimate. 82 of the 85 cars listed here meet these rules. Page 2 lists every other 2021 Mercedes-Benz GLB car, cheapest first, including the 3 the groups do not pick from.

The AskCar estimate is our expected asking price for that one car, from its model, age, mileage and specification, using the 835 priced Mercedes-Benz GLB adverts on AskCar as of 10 November 2026. The figures on this page describe the cars advertised, not a valuation of every 2021 Mercedes-Benz GLB.

Each car: year, make, model, engine and trim, power, gearbox, fuel, body, doors, colour; mileage; price and its changes; how the price compares with the AskCar estimate; emissions standard and ULEZ compliance where it holds; MOT; dealer and town; AskCar page. Each car's AskCar page has its full price history and cheaper cars like it.

This list leaves out 1 car whose advertised mileage is lower than the mileage recorded at its last MOT test.

Best value 2021 Mercedes-Benz GLB: priced furthest below the AskCar estimate

These 10 are priced 6% to 11% under their AskCar estimate. Their asking prices run from £18,990 to £24,250.

Cheapest 2021 Mercedes-Benz GLB: the lowest asking prices

These 10 are priced £15,795 to £18,495. They have covered 59,293 to 101,000 miles.

Lowest-mileage 2021 Mercedes-Benz GLB

These 10 have covered 13,861 to 30,623 miles. Their asking prices run from £20,990 to £32,995.

Recently reduced 2021 Mercedes-Benz GLB: the biggest price reductions in the 14 days to 10 November 2026

The dealer lowered the asking price on each of these 10 in the 14 days to 10 November 2026. Their reductions since AskCar first saw them run from £1,750 to £5,270.

Newly advertised 2021 Mercedes-Benz GLB: first seen by AskCar in the 7 days to 10 November 2026

These 10 are the most recently advertised. Cars first seen on the same day are listed cheapest first.

Mercedes-Benz GLB by gearbox, fuel and body

Mercedes-Benz GLB prices by year

Mercedes-Benz GLB by trim

2021 Mercedes-Benz GLB by trim

Mercedes-Benz GLB by price

Mercedes-Benz GLB near you

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