Inheritance tax is payable on your total 'estate' when you die. A certain portion is taxed at 0%. This is referred to as the Nil Rate Tax Band (NRT). It is also possible for a widowed spouse or surviving civil partner to "use" any surplus of the NRT Band of their deceased spouse/civil partner. Based on the information you have provided, if we feel your estate is likely to be greater that the NRT Band we may contact you to discuss your options.
For more information on inheritance tax click here: www.hmrc.gov.uk/inheritancetax/