To calculate the deduction you apply the business percentage by the interest paid. We recommend preparing a full reconciliation and for this you will need:

• The date the loan was taken out.

• The amount borrowed

• The charges for arranging the loan.

• The payment schedule (ie first payment £250 then 34 monthly payments of £200 with a final payment of £150).

• The business use percentage.

Most of this information will be on the loan agreement documentation.