Yes, but you don't get stung its up to you to inform HMRC on your tax return.
You can find the basic details at:
http://www.moneysavingexpert.com/banking/tax-rates It is payable on just the profit less the annual allowance at 18% until you hit the higher tax band and 28% after that.
One wrinkle that may affect you is whether your property is classed as residential (28% tax) or a holiday home (20% tax if you meet the criteria about minimum number of days available/let).
Your tax office will help you calculate the tax if you provide them with the details in advance however if like most people you submit just before the deadline you have to calculate it yourself.