Claiming Allowable Expenses for Pre-Tenancy Property Improvements: What's the Rule?

I’m seeking clarification on the timing of allowable expenses for rental income. I started renting out my property for the first time in June, but made some improvements to the property in the months prior while I was still living there to make it suitable for renting. Can I claim these improvement costs as allowable expenses, or can I only claim expenses incurred after the tenancy began?

Hi

Usually the rental business does not begin until the first property is let.  Any expenses incurred before the first let must be solely for the rental business and must not be capital expenditure.  
Any qualifying pre-letting expenses are treated as incurred on the day the rental business commences this is usually the day the property is first let.  
So yes you can claim the improvement expenses.  For further information see  PIM2505 - Beginning and end of a rental business: commencement

Thank you