Joint Mortgage Calculator UK
Joint mortgage calculator UK: combine two incomes and shared debts to see an illustrative borrowing estimate when buying with a partner, friend or family member.
How this figure is worked out
Both incomes are combined and the same affordability maths applied, with all shared debts deducted.
- 01
Combine both incomes
Both applicants' gross annual incomes are added together in full before any multiple is applied.
- 02
Apply the income multiple
We use 4.5 times combined income as a representative middle ground for joint applications.
- 03
Deduct combined debts
All monthly debt commitments from both applicants are combined and deducted at the same multiple.
- 04
Add your combined deposit
Your pooled deposit sits on top to give a total property budget and loan-to-value.
Before you apply together
A joint application can increase the income used in an illustration, but it also makes both applicants responsible for the whole mortgage. Read our joint mortgage affordability guide for the practical points to consider before relying on a calculator estimate.
Other situations
Mortgage Affordability Calculator
The standard version for a single, employed applicant.
Self-employedSelf-Employed Mortgage Affordability
Averages your last 2–3 years' income the way lenders actually assess it.
First-time buyersFirst-Time Buyer Calculator
Includes Lifetime ISA bonus modelling to boost your deposit.
Frequently asked
Generally yes — most UK lenders combine both applicants' gross annual incomes in full before applying the income multiple, rather than weighting one income more than the other.
Yes. Lenders assess the application as a whole, so one applicant's credit history, existing debts or financial conduct can affect the outcome and the rate offered, even if the other applicant has a strong record.
Some lenders allow up to four applicants on one mortgage, though not all incomes may be counted in full depending on the lender. This calculator is built for two applicants; for larger groups a broker can advise which lenders accommodate this.
Both applicants remain jointly and individually liable for the full mortgage regardless of any private agreement between them, until the mortgage is remortgaged, transferred, or repaid. This is a legal matter worth discussing with a solicitor before taking out a joint mortgage.