2018 BMW X3 prices under £20,000

There are 141 used 2018 BMW X3 cars for sale under £20,000 from UK dealers on AskCar, as of 7 November 2026. Typical asking price £18,000 (the median: half cost less, half cost more). The cheapest is £11,990. The middle half are priced between £16,500 and £19,000. Median mileage: about 72,000 miles.

Dealers lowered the asking price on more than a third of 2018 BMW X3 cars under £20,000: 62 of the 141 in the 14 days to 7 November 2026.

AskCar lists 3,156 used BMW X3 across the UK, from 1,227 dealerships.

As of 7 November 2026, AskCar lists 601,018 cars and vans from 12,892 UK dealerships, read daily from dealer websites: over 99% of UK dealer used car adverts. No dealer pays to be listed.

2018 BMW X3 cars for sale now under £20,000, page 1 of 3

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. 133 of the 138 cars listed here meet these rules. Pages 2 to 3 list every other 2018 BMW X3 car, cheapest first, including the 5 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 3,052 priced BMW X3 adverts on AskCar as of 7 November 2026. The figures on this page describe the cars advertised, not a valuation of every 2018 BMW X3.

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 3 cars whose advertised mileage is lower than the mileage recorded at their last MOT test.

Best value 2018 BMW X3: priced furthest below the AskCar estimate

These 10 are priced 7% to 12% under their AskCar estimate. Their asking prices run from £15,995 to £19,995.

Cheapest 2018 BMW X3: the lowest asking prices

These 10 are priced £11,990 to £14,600. They have covered 90,244 to 118,000 miles.

Lowest-mileage 2018 BMW X3

These 10 have covered 33,454 to 44,787 miles. Their asking prices run from £17,300 to £19,995.

Recently reduced 2018 BMW X3: the biggest price reductions in the 14 days to 7 November 2026

The dealer lowered the asking price on each of these 10 in the 14 days to 7 November 2026. Their reductions since AskCar first saw them run from £2,000 to £3,345.

Newly advertised 2018 BMW X3: first seen by AskCar in the 7 days to 7 November 2026

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

BMW X3 by gearbox, fuel and body

BMW X3 under £20,000 by gearbox, fuel and body

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