Despite the pandemic 6,752,959 second-hand vehicles changed hands in 2020, compared with 1,631,064 new registrations.
Just as the Ford Fiesta was again the best-selling new car, it was also the most popular used car, according to official figures from the Society of Motor Manufacturers and Traders (SMMT).
Fasten your seatbelts for the top 10 used cars of 2020 – a surprising blend of superminis, family hatchbacks and premium saloons…
The Ford Fiesta has been Britain’s favourite new car for 12 years running and is the biggest-selling car in the UK ever, so it's no surprise to find that it's also the most popular used vehicle.
Originally introduced in 1976, the seventh generation model (pictured) was launched in 2017 and it's the best yet. Affordable, comfortable and well equipped, the Fiesta has always been one of the most engaging cars in its class to drive and there's no shortage of second-hand examples out there.
If connectivity is important, go for the current model or look out for a late, low mileage Mk 6 (2009-17). As for engines, the 1.0-litre EcoBoost petrol turbo (especially the 125PS) is a gem.
A long-time runner-up to the Fiesta in the sales charts, the Vauxhall Corsa now has its best shot at toppling its arch-rival.
The impressive fifth generation car was launched in 2019 and it's the first new model under the ownership of France's PSA Group (Peugeot, Citroen and DS). This means it shares substantial DNA with the latest Peugeot 208, which is no bad thing. It's also available with petrol and diesel engines, plus a 100% electric model.
Whether you go for the new Corsa, or the 2014-2019 Mk 4 (pictured), it's a solid second-hand car choice. Again, there are plenty to choose from, so take your time.
One of Britain's best-selling cars every year since the Mk 1 was launched in 1998, the Ford Focus combines style, good handling and practicality and is available with a wide range of efficient engines.
The Mk 4 (launched in 2018) is a return to form for the family car favourite, but the previous generation is still a sensible used car choice, while earlier models are available at bargain prices.
If you go for a 2011-2018 Mk 3 (pictured) we'd recommend a facelifted post-2014 car powered by the 1.0-litre 125 EcoBoost petrol in Zetec trim.
The Mk 8 Volkswagen Golf was only launched in 2020, so not an ideal time to look for bargains on the second-hand market. A sleek evolution of the previous model in looks, it's now more refined, comfortable and dynamic to drive than ever – and packed with the latest digital technology.
Most second-hand Golfs are likely to be from the previous generations, but we reckon you should target the 2012-19 Mk 7 (pictured) which is still a great drive and should still meet most people's tech needs.
The 1.4 TFSI petrol turbo is a superb engine, the diesels are particularly frugal if you do a high mileage and the Golf R is still one of the best hot hatches out there.
Just like the Corsa has long played second fiddle to the Fiesta, the British-made Astra has never quite matched the Focus.
Good-looking, practical, comfortable and value for money, the current seventh-generation car (2015-) is the best Astra ever boasting a combination of economical engines and an enjoyable driving experience.
If your budget won't stretch to the latest model, then a Mk 6 (2009-16) is still a good used buy. As ever, find one with a full service history and low mileage.
The first of the premium vehicles to make it into the UK's top 10 most popular used cars. Available as saloons, coupes, cabriolets and estates (Tourings), we're now into the seventh generation of BMW's best-seller.
Unveiled in 2018, the latest model (pictured) handles as superbly as ever, it's more spacious and packed with tech. There's also an impressive plug-in hybrid (badged 330e) version.
There's no shortage of used 3 Series cars out there, but choose carefully because they can be expensive to maintain. The sixth gen (2012-18) has a good reputation for reliability, so look out for a full service history, and if you're a high-miler, BMW diesels are some of the sweetest out there.
Retro cool, funky and engaging to drive, the MINI Hatch is made in Britain and is a class act. It’s also generously equipped, well built and packed with quirky design touches and personalisation options.
Third-generation MINIs (2014-) make a great second-hand buy, though there are stacks of older models on sale (2001-06 and 2007-13) that still look great.
It's fair to say that reliability wasn't originally one of the reborn MINI's strongest points, but things have improved over the years. Just remember, it's a premium product so it will cost a little extra to maintain.
One thing's for sure, driving a MINI is a unique experience and superb fun.
Launched in 2018, the sixth generation of Volkswagen's popular supermini looks good, drives well and features a great choice of technology and safety equipment.
Spacious and surprisingly refined, build quality is impressive and overall, it's right up there with the Fiesta, Corsa and Renault Clio at the top of the supermini league.
So, the Polo is a good nearly-new option, but don't overlook the 2001-17 Mk 5 (pictured) which is a solid second-hand buy and is now available at sensible prices. Boasting an efficient range of petrol and diesel engines (we'd recommend the 1.0 and 1.2-litre petrol units), it's easy to drive and well-built.
The fact that a Mercedes-Benz features in the top 10 most popular used cars is perhaps a reflection of the way car finance deals with manageable monthly repayments have made expensive models more accessible.
Winner of the prestigious 2015 World Car of the Year Award, the Mercedes-Benz C-Class is a class act. The latest version (pictured) is more efficient, better equipped and luxurious than ever and makes a great upmarket second-hand car choice.
If you're a high-miler, then the 2.1-litre diesel (badged C220d) could be for you, while the plug-in hybrid is the most frugal of the petrol options.
Go back a generation to the Mk 3 (2007-14), for used C-Class bargains, but only go for a cherished example.
Another German brand with serious badge appeal, the latest Audi A3 was launched in 2020 and is a winning combination of refinement, comfort, build quality and top tech, plus improved driver engagement.
Battling it out with the BMW 1 Series and Mercedes-Benz A-Class at the premium end of the family hatchback sector, there's frankly not much between them.
For a reasonably priced used A3, you'll have to go back a generation to the 2012-2019 Mk 3 (pictured), which still looks sharp today. Available with a wide range of petrol and diesel engines, there's also a plug-in hybrid version.
Do your research and make sure you buy an example that's been well looked with a full service history.
Top 10 new cars of 2020
And finally, just in case you're wondering, here are the most popular new cars of 2020, again according to the SMMT:
I'm an experienced journalist, digital editor and copywriter, now specialising in motoring. I’m editor of Automotive Blog and have worked across the media in newspapers, magazines, TV, teletext, radio and online for household names including the BBC, GMTV, ITV and MSN. I’ve produced digital content in the financial sector for Lloyds Bank, Nationwide and the Money Advice Service. I'm married with two children and live near Bath in Somerset.