I'm not 100% sure how company car tax works. If someone could explain it would be appreciated.

Also how much is a sdv6 per month on the tax?

Fraser  2012 RRS Autobiography, Fuji White all the toys
2011 Audi RS5

Assuming you are talking about taking the car as a benefit via your P11D then:

Very high level explanation

+ Taxable value of the vehicle
- Less contributions made yourself
= Car Taxable Value
x Tax Rate (depends on C02 emissions)
= Taxable Benefit.

You'll then pay tax on the TB at the appropriate rate depending on what bracket you're in.

Check out the HMRC website as the rules are changing. They also have a calculator too  ON THE WAY: BMW F21 M140i
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Thanks bean it's appreciated. Company cars are something I have never looked into. 2012 RRS Autobiography, Fuji White all the toys
2011 Audi RS5

What BC says is correct, but to give you some figures

An HSE is £57k list (doesn't matter if you bought a demo with a discount, or a year old one,it is done on list)
The car has 35% applied to this figure brining the benifit in kind to £19950, this is the figure you are taxed on, so you pay if taxed at 40%, £7980 pa or £665 per month.
That is based on if you are an employee, if a company director 40% becomes closer to 32%.
One reason I chose to get an SE, hate paying the government more than I have to!
Cheers
Dave MY10 TDV6 SE (debadged ), Santorini Black, Flappy paddles, Privacy Glass, 20" Stormers, Mudflaps!

Gone: a comprehensive list of imprezas and a Merc ML AMG