Home / Glossary / Declaration of trust
What is Declaration of trust?
Last verified 23 October 2026
A declaration of trust is a document that records who owns the beneficial interest in a property and in what shares. Beneficial ownership is who is actually entitled to the value and income, which can differ from the names on the title.
Why it matters to landlords
For spouses and civil partners who live together, HMRC splits income from jointly owned property 50:50 by default. To be taxed on your real, unequal shares you send Form 17, and HMRC asks for evidence that your beneficial interests are unequal, such as a declaration or deed. A Form 17 declaration can only be made where you are entitled to unequal shares, and not where you own as beneficial joint tenants. It must state your shares of both the property and the income correctly.
The 50:50 default and Form 17 only apply to spouses and civil partners who live together. For any co owners, a clear record of ownership helps show what share of the income and of any gain each person should report. Because a declaration of trust changes who owns what, take legal advice before signing one, not just tax advice.
Example
A married couple own a rental house 75:25 under a declaration of trust. Without Form 17, its £20,000 profit is taxed £10,000 each. With a valid Form 17, it is taxed £15,000 and £5,000, matching their real shares.
MTD for jointly owned property →
Related terms
- Joint ownership and Form 17
- Capital Gains Tax (CGT)
- Capital Gains Tax annual exempt amount
- Qualifying income
- Limited company buy-to-let