If you receive rental income from a property, you must calculate your taxable profits based on operating a rental income business.
This means that all your UK rental activities form a single business and income and expenditure must be dealt with under proper accounting principles.
All the types of income from land and property in the UK are treated as part of a single business but if you have property income from outside the UK, this is treated as a separate business. If the property is jointly owned, each joint owner’s share is included as part of their property business profits. If the property business makes a loss this can be carried forward and used against future profits of the business.