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6 expensive driving mistakes and how to avoid them

March 18, 2025

When you’re new to driving in the UK, it’s easy to make mistakes. The road signs can be confusing, the roundabouts are enough to make your head spin. And don’t get us started on box junctions. 

Unfortunately, lots of these driving mistakes can leave you stuck with unexpected fines, boosted bills and expensive repairs. None of which make budgeting for life in the UK any easier. 

Luckily, most costly driving mistakes can be swerved with a little know-how and forward planning. Read on to learn how to avoid these six common driving mistakes.

1. Misunderstanding road rules and signs

Learning what different UK road signs, symbols and road lines mean is essential for avoiding driving mistakes in the UK. It’s likely you’ll have learned some of these if you passed your UK driving test. But for those who didn’t, or need a quick refresher, here’s a few rules even locals often get wrong.

Speeding

Speed limits are taken very seriously in the UK and are often monitored by cameras. Get caught driving too fast and you’ll face a fine from £100 upwards and 3 penalty points on your licence (which also can make your insurance more expensive). 

Speed limits in miles per hour are clearly marked on red circle signs with a number in the middle. This will vary depending on the road you’re on but generally the speed limits are:

  • 30 mph in built up areas.
  • 60 mph on single carriageways (roads with no central barrier between lanes).
  • 70 mph on motorways and dual carriageways (unless signs say otherwise).

When driving in congested urban areas or near schools, the speed limit will often drop to 20mph. And on some motorways the speed limit changes for different sections. So it’s very important to pay close attention to the signs.

Stopping in yellow box junctions

A box junction is a yellow box with criss-cross lines painted on the road. You’ll find them at large busy junctions to help keep traffic flowing and prevent gridlock. 

You must not stop within a box junction, so it’s important to wait until your exit from the junction is clear before you enter it. Even if the lights are green. If you’re caught stopped in a box junction you can be fined up to £160 on certain routes in London. 

Getting confused at roundabouts

Not every country in the world has roundabouts like the UK – and they can take some getting used to. Cutting across lanes, not signalling and not knowing who to give way to can lead to expensive accidents and repair costs. 

Driving in bus lanes

Lots of towns and cities in the UK have lanes that can only be used by buses during certain hours. Drive in them at the wrong time and you could face a fine. So no matter how tempting that open bus lane looks during rush hour, stay out. 

Using your mobile phone

Like most places in the world, it’s illegal to use your mobile phone while driving in the UK. This counts even if you’re paused at traffic lights, or adjusting the sat nav on your phone.  

If you’re caught, you could receive up to 6 penalty points on your driving licence and a £200 fine. And if you’ve passed your UK driving test within the last two years? You could also lose your licence. 

For more serious cases, where phone use results in dangerous driving, you could also face a court appearance, a driving ban, and a fine of up to £1,000.

2. Parking fines

Ignoring parking restrictions in the UK can leave you with some big fines.

If a road has double yellow lines by the pavement it means you can’t park there at all. If there’s a single yellow line it means you can park there at certain times. There will be a sign with all this information on it - and you may need to purchase a ticket. 

You nearly always need to pay to park in dedicated car parks – and they’re usually monitored by cameras that record licence plates. Forget to pay or overstay your welcome and you can count on a fine coming your way. 

3. Not paying tolls, congestion and emissions charges

What’s the difference? Keep reading to find out. 

Toll charges

Some roads in the UK, like the Dartford Crossing or the M6, require a payment to use them. This is called a toll charge. 

On some toll roads, the payment is taken on route via a toll booth on the road itself. But some, like the Dartford Crossing, are online only.

While this eases traffic, and cuts out a last minute scramble for cash, it does mean you have to remember to register and pay the toll in advance online, or by midnight the following day. Forget and you’ll get a £70 fine in the post.

Congestion charge

The congestion charge is a fee that most cars need to pay to drive in central London. It costs £15 per day and applies between 7am and 6pm Monday to Friday and between 12pm to 6pm on Saturdays, Sundays and bank holidays. 

You ideally need to pay this charge in advance or on the same day, either online, by auto pay, app or over the phone.

The cost goes up to £17.50 if you pay it late. And you’ll get a £160 fine if you forget to pay at all. 

Ultra Low Emission Zone (ULEZ)

This is another cost of driving in London. And yes, it’s separate from the congestion charge. 

The good news is, not everyone has to pay it. ULEZ charges usually only apply to petrol cars built before 2005 and diesel before 2015, but you’ll need to check your vehicle to be sure.

It’s £12.50 per day to drive inside the M25 (on top of the congestion charge) if you have an older car. If you’re eligible, and forget to pay within three days of your journey, you could get a fine of up to £180. 

4. Forgetting road tax and MOT

Paying road tax on a vehicle is a legal requirement in the UK. You must pay road tax before driving it and then every year after. Otherwise you could face a fine from the Driving Vehicle and Licencing Agency (DVLA) of either £1000 or five times the amount of tax you need to pay. 

Every car over three years old also needs an MOT every year. This is a safety and environmental standards check on your car to make sure it's roadworthy — and it’s a legal requirement. You should be able to find a local approved MOT test centre near you to get a quote. 

It’s your responsibility to remember when your MOT is due. If it expires and you get caught driving, you could face a fine of up to £1000! 

5. Insurance penalties

It’s against the law to drive without car insurance in the UK. If you drive a car that you personally are not insured on, you could get a fixed penalty from the police of £300 and 6 points on your licence.

It also means you should avoid borrowing cars from friends and family. That’s because in the UK, car insurance only covers the people named on a policy to drive a particular car. So unless you’re:

  1.  one of the named people on a policy or
  2.  you have your own insurance that specifically says you’re covered to drive other cars;

You won’t be insured! And could face a fine.

6. Using the wrong fuel

You only need to zone out for a minute to put diesel in a petrol car (or vice versa) but it can cost you hundreds in call out charges and repairs. It sounds obvious but it happens more than you think – and strikes locals and newbies alike.