MX-5 NB · running costs · UK 2026 figures

What an MX-5 NB really costs to run

The NB is cheap to buy and famously cheap to insure — but "cheap" hides a few traps. The honest cost of ownership isn't just fuel and tax; it's the wear items and the corrosion repairs that an older sports car will eventually ask for. Here's the real picture, in 2026 UK money, with the figures broken out so you can see exactly where the money goes.

*For a typical weekend car kept ~3 years at ~4,000 miles/yr, net of resale. Your figure depends on the exact car — run yours here.

The fixed costs (you pay these whether you drive or not)

• Insurance — from ~£350/yr, but age changes everything. The MX-5 is consistently rated the cheapest car in the UK to insure (around £250 on average across all drivers), and a 30–49-year-old on a standard policy pays roughly £350. But age is the single biggest swing: a 25–29 driver pays more like £560, a 21–24 driver around £1,050, and a new 17–20 driver can be looking at £1,900+ — often more than the car itself. A limited-mileage classic policy is cheaper if you qualify (usually 25+); modifying the car typically adds around 40%; and a telematics "black box" can cut young-driver costs significantly.
• Road tax (VED) — ~£415/yr for the 1.8, ~£390 for the 1.6. This depends on the exact registration date and CO2 figure: cars registered before March 2006 are capped, and pre-2001 cars sit on the engine-size basis (~£360). Always confirm the specific car on the DVLA "check vehicle tax" service.
• MOT — ~£55/yr. The statutory cap. Budget separately for whatever the test finds — on an NB that's usually corrosion.

The variable costs (these scale with miles)

• Fuel: a real-world 33 mpg on the 1.8 (36 on the 1.6) works out around 20p per mile at current pump prices. The 1.6 is a little cheaper but you'll work it harder.
• Tyres and routine servicing: roughly 7p per mile amortised — oil and filter annually, tyres every few years. Parts are cheap and plentiful; this is a DIY-friendly car.

The cost nobody budgets for: the risk reserve

This is where most "running cost" articles fall down. An older car carries a backlog of jobs that will come due — a cambelt, a clutch, suspension bushes, cooling, and on the NB, corrosion. You don't pay them every year, but you should be setting money aside as if you do.

We model this the way a quantity surveyor models contingency: each known fault has a cost and a probability, and the two multiplied together give an expected reserve. For a typical usable NB that reserve runs into several hundred pounds a year; for a project with structural rust it can dwarf every other cost combined. Ignoring it is how people end up "spending £3,000 on a £2,000 car."

The offset: it's appreciating

Here's the good news that generic cost calculators get wrong. They assume every car loses 10% a year. A sound NB doesn't — clean examples are flat to slowly appreciating. So while you'll spend real money running it, most of your capital survives: buy well and the car gives a lot of it back when you sell. That's what makes a good NB one of the cheapest ways to own a proper sports car.