Increasing BTL mortgage - Tax Relief

I increased my BTL mortgage in 2019. I have been claiming the whole amount of interest against income tax. I increased the sum so that I could reimburse myself of the various costs that I have incurred running the rental property and to provide capital for further expected costs. In your document 'Work out your rental income when you let property - GOV.UK', in the section 'Increasing your mortgage', HMRC say '...you may be able to treat interest on the additional loan as a revenue expense, or get relief against Income Tax as long as the additional loan is wholly and exclusively for the purposes of the letting business.' I have not been able to find anything more on the subject, though I have seen a comment to the effect the interest can be used for expenses, Unfortuantely I am unable to find the document again. Are you able to provide further clarity on this or direct me to any published HMRC guidance in relation to what is considered acceptable to HMRC?

Hi ,
 

If you increase your mortgage loan on your buy-to-let property you may be able to treat interest on the additional loan as a revenue expense, or get relief against Income Tax as long as the additional loan is wholly and exclusively for the purposes of the letting business. Interest on any additional borrowing above the capital value of the property when it was brought into your letting business is not tax deductible. If the mortgage is for a residential property then the restrictions on interest from April 2017 will apply.  Please also see : Property Income Manual   . Thank you .