The first time buyer’s £250,000 threshold applies from 25 March 2010 up to 24 March 2012 inclusive.
You must both be first time buyers. That means neither of you should have owned a property before. If you are not sure if you qualify then just call them – The Stamp Taxes Helpline on 0845 603 0135.
You have to be buying it as your home – not as an investment.
You must also not have inherited a property or jointly owned one.
There is a list of questions on this Questions about Stamp Duty pdf file from HMRC which might help with any further queries – but their helpline is there to assist you more.