The default for spouses
Where property is held jointly by a married couple or civil partners living together, HMRC treats the income as split 50:50, whatever the actual ownership shares are.
How Form 17 works
If your beneficial interests are genuinely unequal, for example 90:10, you can jointly sign Form 17 and be taxed on those shares. A declaration of trust is usually needed to create or evidence the unequal ownership. The form must reach HMRC within 60 days of the later signature. It can't be backdated and you can't pick the split you want: it must match real ownership.
Why it matters more from 2027
With property income taxed at 24%/44%/49%, shifting income from a higher-rate spouse to a basic-rate spouse saves 20 points on each pound moved. On £10,000 of rent that's £2,000 a year. Changing ownership has legal, mortgage and CGT effects, so take advice first.
Unmarried co-owners
Unmarried co-owners can agree how profits are shared, and each reports their share. MTD thresholds also use each person's share of gross rent.
Frequently asked questions
Can we choose any split on Form 17?
No. It must reflect your actual beneficial interests in both the property and the income.
Sources
- GOV.UK: Declare beneficial interests in joint property and income (Form 17)
- GOV.UK: Work out your rental income when you let property
- GOV.UK: Making Tax Digital for Income Tax
Sources last checked 9 November 2026. See all our sources and how we keep pages up to date.