Property Ownership for Unmarried Couples: Tax Implications 2026

Buying a home together is one of the biggest financial decisions any couple makes. If you are not married or in a civil partnership, the tax and legal landscape looks very different — and in many cases, less favourable. Understanding the rules before you buy can save you thousands of pounds and prevent serious disputes if the relationship breaks down or one partner dies.

This guide sets out the key tax implications of property ownership for unmarried couples in the UK using 2026/27 rates.

How You Own the Property Matters

When two people buy property together in England and Wales, they can hold it in one of two ways:

Joint tenants — both partners own the whole property together. If one partner dies, the other automatically inherits their share through the right of survivorship, regardless of what any will says. You cannot leave your share to anyone else.

Tenants in common — each partner owns a defined share, which can be equal (50/50) or unequal (for example, 70/30). Each partner can leave their share to whoever they choose in a will.

Choosing the right structure at the outset is not just a legal formality. It affects how rental income is taxed, how Capital Gains Tax is calculated on a future sale, and what happens to the property on death. Switching between structures later is possible but involves legal costs.

A Declaration of Trust (also called a Deed of Trust) is a legal document that sets out each partner's ownership percentage, how costs and income are shared, and what happens if the couple separates. Solicitors typically charge £200–£500 for one, but it provides clarity that is worth far more if things go wrong.

Stamp Duty Land Tax for Unmarried Couples

Stamp Duty Land Tax (SDLT) rates are not directly affected by whether you are married. The standard residential rates apply equally.

However, the 3% higher-rate surcharge (which rose to 5% in October 2024) for additional dwellings can catch unmarried couples off guard. The rule is applied per transaction: if either buyer already owns a residential property anywhere in the world, the higher rate applies to the entire purchase.

This matters for unmarried couples because each partner is assessed individually in terms of property history, but the surcharge applies if any buyer in the transaction owns another property. If you are buying together and one partner already owns a flat, you will both pay the higher rates on the new purchase.

For a property purchased at £350,000 where neither partner previously owned property:

• First £125,000 at 0% = £0
• £125,001–£250,000 at 2% = £2,500
• £250,001–£350,000 at 5% = £5,000
• Total: £7,500

If the higher-rate surcharge applies, add 5% to each band, increasing the total significantly. Use our stamp duty calculator to model your exact liability.

Income Tax on Rental Income

If you let out a jointly owned property, the rental profit must be declared to HMRC. How that profit is split between partners for tax purposes depends on your ownership structure.

For joint tenants, HMRC automatically assumes a 50/50 split. You cannot alter this without changing the ownership structure.

For tenants in common, the split follows your actual ownership shares. This creates a legitimate planning opportunity: if one partner is a basic-rate taxpayer (paying 20% on income between £12,571 and £50,270) and the other pays higher rate (40% on income above £50,271), holding more of the property in the lower earner's name reduces the overall tax bill.

For example, if the rental profit is £10,000 per year and you hold the property 70/30 in favour of the lower earner:

• Lower earner receives £7,000, taxed at 20% = £1,400
• Higher earner receives £3,000, taxed at 40% = £1,200
• Total tax: £2,600

A 50/50 split would produce:

• Each receives £5,000; lower earner pays £1,000, higher earner pays £2,000
• Total tax: £3,000

The tenants in common structure saves £400 per year in this example. Over a decade, that is £4,000 — more than enough to cover the cost of a Declaration of Trust and professional advice.

Remember that mortgage interest relief is now restricted to a basic-rate tax credit of 20% for residential landlords, regardless of your personal tax rate.

Capital Gains Tax When You Sell

When you sell a jointly owned property that has increased in value, Capital Gains Tax may apply on the gain. For 2026/27:

• The Annual Exempt Amount (AEA) is £3,000 per person
• Residential property gains are taxed at 18% for basic-rate taxpayers or 24% for higher and additional-rate taxpayers

Because each partner is taxed on their own share of the gain, a jointly owned property gives you two sets of AEA to use — up to £6,000 combined before any CGT applies.

If the property is your main home and qualifies for Private Residence Relief (PRR), the gain may be fully or partially exempt. PRR covers the period you lived in the property as your main residence plus the final 9 months of ownership. Both partners must live in the property as their main home for the relief to apply in full to both.

If only one partner lives in the property (perhaps the other keeps their own separate home), that partner's share may be fully exempt while the absent partner's share is fully taxable.

For complex CGT calculations involving multiple properties, professional advice is strongly recommended.

Inheritance Tax: The Biggest Risk for Unmarried Couples

Inheritance Tax is arguably the area where unmarried couples face the starkest disadvantage compared to married couples or civil partners.

Married couples and civil partners benefit from an unlimited spousal exemption: transfers between them are completely free of IHT, both during life and on death. There is no such exemption for unmarried partners.

For 2026/27, each person has:

• Nil-Rate Band (NRB): £325,000 — no IHT up to this threshold
• Residence Nil-Rate Band (RNRB): £175,000 — available when a main residence passes to direct descendants (children, grandchildren)

The RNRB is important: it applies when the property passes to direct descendants, not to an unmarried partner. If a property worth £500,000 is held as tenants in common and one partner dies leaving their 50% share (worth £250,000) to the surviving partner, IHT is calculated using only the deceased's NRB.

If the deceased had no other estate, the £250,000 share falls within the £325,000 NRB and no IHT is due. But if the deceased had other assets (savings, investments, life insurance), the NRB may already be used up, and the property share could face a 40% IHT charge.

Critically, the unused NRB and RNRB of a deceased unmarried partner cannot be transferred to the surviving partner. Married couples can combine their allowances (potentially £1,000,000 total including two RNRB allowances); unmarried couples cannot.

Practical steps to reduce IHT exposure:

• Write a will — without one, your share passes under intestacy rules, which give nothing to an unmarried partner
• Consider life insurance written in trust to cover a potential IHT liability
• Take specialist estate planning advice if the combined estate exceeds £325,000
• Explore whether equalising the estate between partners could help over the long term

Mortgage and Income Tax Considerations

If you are applying for a joint mortgage, lenders assess both partners' income. This can be advantageous if both earn well, enabling you to borrow more. Most lenders allow joint mortgages for unmarried couples without restriction.

However, if the relationship breaks down, a joint mortgage leaves both parties liable for the full debt. One partner cannot be removed from a mortgage without the lender's consent, which typically requires a full affordability assessment.

If one partner earns significantly more, it can sometimes make sense for that partner to take the mortgage in their sole name, while the other partner's contribution is recorded via a Declaration of Trust. Get legal and financial advice before proceeding, as this affects both borrowing capacity and tax efficiency.

Cohabitation Agreements and Legal Protection

A cohabitation agreement is a legal contract between two people living together that sets out financial arrangements if the relationship ends. It can cover:

• Who owns what share of the property
• How bills and mortgage payments are divided
• What happens to the property if you separate

Unlike marriage, there is no automatic financial settlement for unmarried couples in England and Wales if the relationship ends. Courts have very limited powers to redistribute assets. A cohabitation agreement, while not absolutely binding, provides strong evidence of the parties' intentions and is taken seriously by courts.

Combined with a Declaration of Trust and up-to-date wills, a cohabitation agreement forms the legal foundation that gives unmarried property owners the protection they need.

Planning Your Property Ownership Structure

Before buying together, consider these steps:

1. Agree on ownership structure — joint tenants or tenants in common, and if the latter, in what shares
2. Prepare a Declaration of Trust — especially if contributions to the deposit or mortgage differ
3. Write wills — so each partner can direct their share as they choose
4. Review IHT exposure — particularly if the combined estate is likely to exceed £325,000
5. Assess income tax on rental — if you plan to let, the ownership split affects how rental profits are taxed
6. Understand CGT on sale — plan for Private Residence Relief and the use of both AEAs
7. Consider life insurance in trust — to cover mortgage and potential IHT on death

Regular reviews matter too. If one partner's income changes significantly, or if you acquire additional property, the optimal structure may shift.

---

This article is for information only and does not constitute financial or tax advice. Tax rules may change. Consult a qualified adviser for your specific situation.