How Lenders Calculate Commission Income
The approach to commission income varies between lenders. The most common method is to take a twelve or twenty-four month average of actual commission received and use that average as an ongoing income figure. Using a longer period of twenty-four months is more conservative but also more stable, as it smooths out a single exceptionally good or exceptionally poor year.
Some lenders will use 100 per cent of your average commission, while others apply a haircut — perhaps taking only 50 to 75 per cent of the average figure — to reflect the variability inherent in commission earnings. The proportion used depends on the lender's risk appetite and the sector you work in. Roles where commission is highly predictable and tied to recurring or renewal income may attract a more favourable treatment than those involving more speculative sales activity.
Your base salary is typically assessed in full, with the commission element added at whatever percentage the lender's criteria allows. The combined figure is then used in standard affordability calculations alongside your existing commitments to determine how much you can borrow.
Income Evidence for Commission-Based Applications
To support a commission-based secured loan application, you will typically need to provide twelve to twenty-four months of payslips showing both your base salary and commission payments. Where commission is paid monthly, this is straightforward. Where it is paid quarterly or annually, providing an explanation of the payment structure alongside the payslips is helpful.
Your most recent P60 tax summary is also a valuable document as it shows your total gross earnings for the tax year, including commission, verified by HMRC. P60s for two years provide the twenty-four month income history that many lenders prefer. Bank statements covering the same period as your payslips will corroborate the income receipt and show how your earnings fluctuate throughout the year.
If your commission income has varied significantly between years — for example, due to a change in role, a difficult trading period or a bumper year — providing an explanation helps the underwriter contextualise the data. A lender who understands why income varied can make a more informed decision than one working from raw numbers alone.