It's a difficult one, depending on what side of the fence it is that you're on.
Companies with large fleets obviously get substantial discounts on the costs of vehicle running costs and you, personally, wouldn't be able to run a car for that amount.
Having a company car will usually enable you to have something better than you would have privately, at less cost to you.
However, if you are on a company pension scheme with them paying a percentage of income into your pot and you've taken salary in lieu of a car then, depending on the set up, more could be getting paid into your pension.
If you're doing 25k mpa in your own car, that translates into £7750 expenses per year, tax-free. You could probably arrange a leasefor say £500 inc VAT for a reasonable car, add another £100 or so if you want the servicing and tyres in on it as well, so you can see that from that alone you won't have much left for fuel, VED (after the first year) and insurance (which will be higher, as you're using it for work). However, there is the salary in lieu to add in. Say fuel will be an ave of 35mpg at 130ppl for diesel, so for 27k mileage gives 3507 litres = £4559 plus say £400 insurance and £200 VED. So you'd need a total of 12x600 + 4559 = 600 = £12359pa to breakeven and knocking off the mileage expenses gives a required salary increase of £4609.
It's been about 4 years since I was a director of a company with other than myself in its employ and I think we used to offer £2.5k salary increase or thereabouts instead of a car, on the basis that we did not expect to be funding their private use of it as well (which the figures above do, of course). If they offer you say £3k, then you're getting use of a good quality vehicle for £1.5kpa, or 75ppm. Don't forget you will pay NICs on either BIK or additional salary.
Advantage of a company car? If you have free choice, you will tend to get something better than would be the case if it was yours; no worries re running the thing; if you lose your job, you don't have to stump up the dosh to keep it going; don't need to attain company mileages to make your figures work. Downside? BIK tax; leave job, lose car; possible restriction of choice; subject to vagaries in the tax regime (eg when Brown came in, my CCT doubled overnight).
Either way, unless you run an old banger and are lucky with servicing and spares costs through the year, having a car will cost you.
Alternatively, use your company car strictly for company use (difficult if you go to and from work) and get an old crate for private use. No private use of company car = no BIK = no tax.
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