Depends on your engine, which you have not indicated.

You are in the UK. Your government's VCA and DVLA Web sites have all the
info you need.

Check out your car's CO2 emissions here:
http://www.vcacarfueldata.org.uk/search/search.asp

Then go here to see the road tax applicable:
http://tinyurl.com/25etq
(link to the correct DVLA site)

More info if you're interested:
http://www.dvla.gov.uk/vehicles/taxation.htm