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HMRC internal manual

Capital Gains Manual

Private residence relief: letting: complete relief on part let

A dwelling house is sold at a gain of £100,000 in 2014. 70 per cent of the dwelling house has been lived in by the owner throughout his period of ownership as his only or main residence. The remaining 30 per cent has been let throughout as residential accommodation.

The computation is

Net gain     100,000
Private residence relief 70%     70,000
Relief under Section 223(4) limited to the lowest of      
  Private residence relief 70,000  
  TCGA92/S223(4)(b) 40,000  
  chargeable gain by reason of the letting 30,000  
applicable relief     30,000
Chargeable gain