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BTL Affordability Calculator

Calculate how much you can borrow for a buy-to-let property. Checks if your rental income meets UK lender requirements.

Typical: 4.5% - 6.5%

Lenders require rental income to exceed mortgage payments by this percentage

How BTL Affordability Works in the UK

Buy-to-let mortgages are assessed differently from residential mortgages. Lenders focus primarily on the rental yield rather than your personal income. This makes BTL affordability calculations essential before purchasing an investment property.

The Rental Coverage Ratio

UK BTL lenders typically require your rental income to cover 125% to 145% of your mortgage payments. This buffer accounts for:

  • Void periods (when the property is empty)
  • Interest rate increases
  • Unexpected maintenance costs
  • Legal and insurance expenses

Maximum LTV for Buy-to-Let

Most high street lenders cap BTL mortgages at 75% loan-to-value. This means you need at least 25% deposit. Some specialist BTL lenders may offer higher LTVs (up to 85%) but typically charge significantly higher interest rates.

Interest-Only vs Capital Repayment

The vast majority of UK BTL mortgages are interest-only. Your monthly payments cover only the interest, keeping costs lower and cash flow better. The capital (original loan amount) is repaid at the end of the term, usually through selling the property.

Important: This calculator provides estimates only. Individual lender criteria vary significantly. Always consult a qualified mortgage broker for accurate affordability assessments.

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Not financial advice. Calculations are estimates based on typical UK BTL lender criteria. Always verify with a qualified mortgage broker.