My NHS and private mix changed last year. Which figure will they use?

A lender does not separate the two. NHS income and private income are both simply income, and no lender applies a different treatment to one than the other. If your mix moved from mostly NHS to mostly private last year, that on its own changes nothing about how you are assessed.

What a lender is watching instead is whether the structure you trade through stayed the same. If you were a sole trader before and you are a sole trader now, or if you held 100% of your limited company before and hold 100% of it now, the figures across the two years are comparable and are treated as comparable. A change in trading status is the thing that resets the picture – not a change in where the work came from.

That leaves the real question, which is which year’s figure gets used. The answer varies by lender rather than by the nature of the income, and it is the same variation that decides how far back your accounts have to go. Some lenders average your last two years. Others take the most recent year on its own.

That matters more than it sounds, because a shift towards private work is often a shift upwards. If your income rose, a lender that averages two years will lend against a figure lower than what you now earn, and one that takes the most recent year will not. If it fell, the same choice works the other way round and averaging is your friend.

So the mix is not the issue and does not need explaining. Which lender reads the years, and how, is the issue.