Buy to Let calculator

Find out how much your client can borrow

Rent and Buy to Let mortgage

Our Buy to Let calculator helps you to check two calculations, both of which must fit our criteria.

Firstly, we check that the rent meets our minimum rental cover at the BTL affordability rate (based on interest only). View our BTL affordability criteria for full details.

Secondly, we also check if the property is self-financing which means the rent covers BOTH 100% of the mortgage at our BTL affordability rate (based on the chosen repayment method) AND the running costs of the property.

You will need to complete all steps in this calculator to confirm the amount we can lend.

Please enter an amount.
Please enter the estimated property value. Our minimum property value is £75,000.
Please select yes or no.

We may be able to lend your client up to:

This is based on {affordabilityRatio}% rental coverage at {interestRate}% on an interest only basis.

Please enter details of the mortgage your client requires

Please enter the Buy to Let mortgage required. Our minimum loan size is £25,000. Our maximum loan size is £750,000. The maximum LTV we can consider is 75%. For New Build flats the maximum LTV is 70%.
Please select the repayment method.
Please enter the interest only amount.
Our minimum term is 5 years. Our maximum term is 25 years.

Monthly running costs

To help us check the property is self-financing we need to assess the monthly running costs for the property.

We consider the property to be self-financing, if the rent covers both 100% of the mortgage at our BTL affordability rate (based on the chosen repayment method), AND the running costs for the property.

Important information

For all applications we will assess the plausibility of the monthly running costs and we may require evidence.

When you submit the full mortgage application please provide as much information as possible to explain the amounts entered. This will help to avoid underwriting delays.

Gross monthly rent

Monthly mortgage amount

Please select whether or not an agent will be used to manage the property.
Please enter the monthly agent’s fees. This amount will vary depending on the agent and the level of service provided.
You must enter a monthly allowance for the loss of rental income to cover periods where the property is empty. We've calculated a guideline figure. If your client's allowance for rental voids is different please change the amount.
We expect your client to make a monthly allowance to cover the costs of maintaining the property.
If the property is or will be leasehold, please enter the monthly equivalent costs for ground rent and service charge. Enter zero if it's not a leasehold property.
Please enter the amount for any other monthly costs that will be incurred to cover things like insurances or safety certificates.
Please include any other costs that your client will use any surplus rent for. For example, if your client will be using some of the income to fund regular living expenses.


  • This amount is subject to a satisfactory valuation.
  • View our Buy to Let lending criteria for information on minimum income, secured credit commitments, maximum number of Buy to Let properties and our valuation policy.
  • We may require supporting evidence to help us assess the plausibility of the monthly running costs.
  • You can save a copy of these results for your records and to help you submit the application on Introducer Internet.



Property value

Mortgage required

Repayment method

Interest only


25 years

Gross monthly rent

Is this a remortgage application where the balance will be the same amount
or less than it was on 31 December 2016 (product fees can be added)?

Interest only amount

Please input the following figures on Introducer Internet

If your client would like to make an application for , which is the maximum we could lend, please see information below on how to submit on Introducer Internet.

AIP > Loan Required > Loan Details

Loan details
Mortgage required £
Purchase price/valuation £
Annual rental income
in respect to this property

FMA > Loan required > BTL details

BTL property self-financing assessment
Gross monthly rent £0
Monthly mortgage payment £0
Monthly agent's fees (if applicable) £0
Monthly allowance for rental voids £0
Monthly property maintenance (see help text) £0
Other monthly costs (see help text) £0
Other monthly commitments to be paid from rent £0
Surplus /(deficit) £0

Any additional information

For all applications we will assess the plausibility of these costs. Please provide as much information as possible here to explain the amounts entered as this will help us underwrite your case quicker.

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