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HMRC internal manual

Property Income Manual

Deductions: main types of expense: costs due to common ownership

In a block of offices or flats there may be separate parts of the building that are not let out but are used in common by the tenants. If so, the landlord can deduct expenditure on the upkeep of the common parts from their rental business profits.

However, the deductions for the common parts may need to be restricted if the landlord uses part of the property privately or there are uncommercial lettings, see PIM2130.