A useful mortgage calculator checklist should include your gross annual income, regular outgoings, deposit, loan term and an estimate of the interest rate. Remember to include council tax, utilities, insurance, travel, childcare, credit commitments and other household spending, as lenders assess affordability rather than just salary. Try different rates and terms to see how repayments could change, and allow for possible rate rises if considering a variable or tracker mortgage. Calculator results are estimates, so an FCA-authorised mortgage adviser or lender will need to assess your individual circumstances before making an offer.