2021 Mercedes-Benz GLS prices

There are 9 used 2021 Mercedes-Benz GLS cars for sale from UK dealers on AskCar, as of 10 November 2026. The cheapest is £42,995.

Dealers lowered the asking price on more than half of 2021 Mercedes-Benz GLS cars: 5 of the 9 in the 14 days to 10 November 2026.

AskCar lists 148 used Mercedes-Benz GLS across the UK, from 113 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 GLS cars for sale now

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. All 9 cars listed here meet these rules.

The AskCar estimate is our expected asking price for that one car, from its model, age, mileage and specification, using the 142 priced Mercedes-Benz GLS 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 GLS.

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.

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

Their asking prices run from £42,995 to £87,995.

Cheapest 2021 Mercedes-Benz GLS: the lowest asking prices

These 9 are priced £42,995 to £87,995. They have covered 13,000 to 84,000 miles.

Lowest-mileage 2021 Mercedes-Benz GLS

These 9 have covered 13,000 to 84,000 miles. Their asking prices run from £42,995 to £87,995.

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

The dealer lowered the asking price on each of these 5 in the 14 days to 10 November 2026. Their reductions since AskCar first saw them run from £1,500 to £8,100.

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

These 2 are the most recently advertised. Cars first seen on the same day are listed cheapest first.

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