Band G

Let's face it... you aren’t likely to find any tax busters in this band! At £400 for 12 months’ road tax, it’s clear cars emitting more than 225g/km of CO2 are the main target for the Government as it looks to clamp down on big polluters.

But Band G isn’t simply packed with top-end supercars and 4x4s as environmentalists would have us believe. Aside from Band A, the top bracket accounts for the fewest number of vehicles on the road. Indeed, in 2006, around 130,00 Band G cars were sold – compared to a whopping 3.5 million in Band F.

Of course, the likes of the Bugatti Veyron – the biggest polluter at 574g/km – Lamborghini Murciélago (500g/km), Ferrari 599 GTB (490g/km) and Bentley Azure (465g/km) are top of the spectrum, both in price and emissions.

In reality, if you can afford a £175,000 car, then £400 a year is a drop in the ocean. The real surprise is the fairly unassuming cars in the same band. Take the Peugeot 807 2.0 auto, for instance. The MPV starts at £22,895, yet a CO2 output of 229g/km means it costs £400 annually. Opting for the diesel adds £1,200 to the list price, but saves £190 a year in tax.

In fact, it’s amazing that any drivers would choose petrol over diesel in an MPV or off-roader. Going for the petrol Nissan X-Trail 2.5 over the 2.0 dCi improves pace slightly, but economy drops by 10mpg, emissions rise to 230g/km and it will add £190 in road tax.

Of course, some enthusiasts still cite performance as a reason to go for petrol, but even that’s hard to justify when modern diesels are so good. Saab’s 9-3 Sportwagon 2.8 V6 Aero emits 250g/km, and while it’s quick, the 1.9 TTiD’s 8.0-second 0-60mph time is only 1.5 seconds slower, yet it costs £145 a year to tax. Of course, diesel isn’t always cheaper. Big oil-burners such as the Audi A8 3.0 TDI LWB (227g/km), Land Rover Discovery TDV6 (249g/km) and Chrysler Grand Voyager 2.8 CRD (247g/km) sit in Band G – so there’s no benefit from choosing diesel or petrol here. If you want something as capable as the Disco or luxurious as the A8, you’re unlikely to find a model that costs less to tax. But there are cash-saving alternatives to other big polluters.

Instead of a BMW M Coupé or Roadster, both of which emit 292g/km, a cheaper tax choice is the Band F Porsche Boxster or Cayman (222g/km). The BMWs are faster – but the Porsche models are superb to drive.