Current:
Up to £175,000 (until 31/12/09) Stamp Duty Land Tax (SDLT) on residential properties = 0%
Then, up to £250,00 SDLT = 1%
Then, up to £500,000 SDLT = 3%
Over £500,000 SDLT =4%
From 01/01/10:
As above but the lower level reverts to £125,000
There is a currently total exemption of SDLT on new homes complying with 'zero carbon' standards where the purchase price does not exceed £500,000. (Above that figure SDLT is calculated at 4% but then reduced by £15,000). The exemption applies until 30/09/12.
There are special provisions for properties in designated disadvantaged areas, where the lower threshold for SDLT will be £150,000 from 01/01/10.
For further information, see here:
http://www.hmrc.gov.uk/sdlt/
Chris