Buying a House With a Partner: Joint Ownership in 6 Countries

Buying a house with a partner means picking one of two ownership modes — equal-and-automatic (UK joint tenants, French tontine) or share-and-bequeathable (UK tenants in common, French indivision, Spanish proindiviso, German Bruchteilseigentum, Dutch eenvoudige gemeenschap, Portuguese compropriedade). The mode you sign decides who inherits if one of you dies, who can force a sale, and how big the tax bill is on the buyout. Most couples sign whatever the conveyancer puts in front of them. Six months later the consequences start to show.

The short version:

• Two modes everywhere, six different names. UK joint tenants vs tenants in common; French indivision (with or without notarial shares); Spanish proindiviso with named cuotas; German Bruchteilseigentum; Dutch eenvoudige gemeenschap with shares set in the deed; Portuguese compropriedade with declared quotas.
• Death of one owner has opposite defaults. In England and Wales, joint tenancy hands the whole property to the survivor and overrides any will. Everywhere else on this list, the deceased's share follows their will or statutory heirs — and an unmarried partner inherits nothing unless named.
• Breakup buyouts are taxed, and the tax varies eight-fold. Spain charges only AJD around 0.5–1.5% on the share transferred. Germany charges full Grunderwerbsteuer of 3.5–6.5%. France charges 2.5% droit de partage to unmarried co-owners — not the 1.1% reserved for divorces and PACS dissolutions (BOFiP, art. 746 CGI).
• The cohabitation agreement is the cheapest legal insurance you'll ever buy. £300–£4,000 in the UK, €300–€600 in the Netherlands, €1,000–€2,500 for a French convention d'indivision.
• The "who paid what" record matters more than the deed. Mortgage statements show the joint account; they don't show who funded it. Every buyout calculation eventually asks the same question.

Buying a house with a partner: the two modes in each country

A 60-second lookup table before the rest:

The pattern: only married couples get an automatic-merger default. Unmarried buyers on the continent get the share-based mode by default, which is — counter-intuitively — the safer setting on death because your will controls your share. The UK is the outlier: cohabiting buyers there get joint-tenants-as-default unless they actively ask the conveyancer for tenants in common, and survivorship wipes out any will on the property.

What happens if one of you dies?

If you're unmarried, the default of joint tenancy in England and Wales sends the property to the survivor automatically — but everywhere else, the deceased's share follows their will, and an unmarried partner inherits nothing unless explicitly named. This is the single biggest gap between common-law and civil-law defaults, and it surprises every cross-border couple who skim-reads the deed.

• UK joint tenants: survivor takes the whole property; the will is ignored on this asset. To preserve control of your share, register as tenants in common with a Form A restriction at HM Land Registry and write a will.
• France indivision: the share belongs to the deceased's heirs under forced-heirship rules — children come before the partner. Cohabitants are not heirs at law. PACS partners have intermediate rights but still no automatic inheritance of the share.
• Spain proindiviso: the share goes to the deceased's legítima heirs unless a will redirects it. Spanish law lets you freely dispose of at most one-third in most regions; the rest is reserved for children or other forced heirs.
• Germany Bruchteilseigentum: the share is independently inheritable. An unmarried partner is not an heir at law. Germany's gift-tax allowance between unmarried partners is just €20,000, with rates up to 30% on anything above it — make this paragraph one of the notary appointment, not an after-thought.
• Netherlands: under an eenvoudige gemeenschap, the share passes by will or intestate succession. A 2023 Hoge Raad ruling confirmed unmarried cohabitants have no automatic compensation rights from the gemeenschap alone — only the samenlevingscontract creates them.
• Portugal compropriedade: the share passes to legitimate heirs. The surviving co-owner gets a direito de preferência on any later sale by those heirs, but no claim on the inheritance itself (CGD Saldo Positivo).

The fix is the same everywhere on the continent: a will that names the partner is the only document that defeats the statutory default. For UK buyers, Form A + tenants in common + a will does the same job, with the added benefit of letting each partner direct their own share independently.

What happens if you split up? The buyout, country by country

This is the question with the biggest tax surprises. The starting assumption — one partner keeps the house and pays the other out — is a property transfer, and most countries tax it.

• UK: Stamp Duty Land Tax applies to the consideration (share value plus the mortgage debt assumed) above the threshold. For unmarried couples there's no automatic divorce-style relief, and Capital Gains Tax may apply if it isn't the main residence. The contemporaneous deed of trust is what locks in the split before it's contested.
• France: out of indivision via partage. Unmarried partners pay the full 2.5% droit de partage under Article 746 CGI on the net value of the indivision. The reduced 1.1% rate is reserved for divorces and PACS dissolutions, per the French tax authority's official guidance — concubinage is explicitly excluded. A 7 April 2026 reform of Article 815-6 of the Civil Code now lets a single co-owner ask the judicial court to authorise the sale without proving the other refused, per Wargny-Lelong notaires.
• Spain: the cheap exit. Extinción de condominio is taxed as Acts Documented in Law (AJD) only — around 0.5–1.5% depending on autonomous community (Madrid: 0.75%) on the share transferred, not the full ITP rate of 6–10%. Watch the exceso de adjudicación trap: if the cash compensation doesn't match the share value, the tax authority can recharacterise the transaction as a sale and levy full ITP.
• Germany: full Grunderwerbsteuer — 3.5% in Bavaria, up to 6.5% in Brandenburg, North Rhine-Westphalia, the Saarland, Schleswig-Holstein and Thuringia — on the share's value. The Bundesfinanzhof has confirmed unmarried separation transfers are not privileged. Married couples in divorce-related transfers are exempt under §3 GrEStG; cohabitants are not.
• Netherlands: overdrachtsbelasting applies to the share acquired. From 1 January 2026 the rates are 2% if the buying partner lives in it as their main residence, 8% if it becomes a second home (the new rate, down from 10.4%), and 10.4% on non-residential property (Belastingdienst). The first-time-buyer exemption is single-use, so it usually doesn't apply on a buyout.
• Portugal: the compropriedade exit triggers IMT on the share's value (sliding scale 0%–7.5% depending on band) plus stamp duty of 0.8%. The other co-owners' direito de preferência gives them eight days under Article 416 of the Civil Code to match any third-party offer.

The lesson: before you sign, model the breakup tax in your country. A clean Spanish split costs around 1% of the share value; an unmarried German split costs 3.5–6.5%. Same situation, different country, a tenfold gap. The cost is part of the true cost of buying a house — most "fees" tables omit the exit-cost line entirely.

Should we be joint tenants or tenants in common?

For UK unmarried couples, tenants in common is almost always the right answer. It preserves your share if you split, lets a will direct it on death, and is the only mode that supports unequal contributions cleanly. Joint tenants is the natural default for married couples whose stated wish is for the survivor to inherit — but even there, many switch to tenants in common to give themselves flexibility on inheritance tax planning.

For continental buyers the question is framed differently: the share-mode is the default, so the real choice is what shares to declare on the deed. A 50/50 deed where one partner paid the deposit and 70% of the mortgage will be revisited — by a court if necessary — when the relationship ends. The contemporaneous record beats the post-hoc reconstruction every time.

How do we split the mortgage when we earn different amounts?

The three patterns that hold up over a decade:

1. Equal split, equal share. Simplest. Works when incomes are within ~20% of each other.
2. Proportional split, equal share. Each pays a fixed percentage of net income; both still own 50%. Requires a written agreement so the higher earner can't later claim a larger share — and so the lower earner isn't penalised for the smaller absolute contribution.
3. Proportional split, proportional share. The deed records the actual capital contributions (deposit plus mortgage paydown plus material capital improvements). Most flexible; requires a contemporaneous ledger of every shared payment for as long as you both own the house.

Pattern 3 is the only one that survives an unequal renovation spend, a parental gift to one side, or a salary divergence five years in. It also requires real bookkeeping — which is the friction point that breaks most couples' good intentions in the first eighteen months.

The cohabitation agreement: paperwork that actually pays

If you're unmarried and buying together, a cohabitation agreement is the cheapest legal insurance you'll buy. UK costs £300–£4,000 per HomeOwners Alliance; a French convention d'indivision through a notaire runs €1,000–€2,500; a Dutch samenlevingscontract €300–€600; a Spanish pacto de convivencia €200–€600; a German Partnerschaftsvertrag €500–€1,500; a Portuguese contrato de coabitação €300–€700. What it locks in: contribution split, what counts as a joint expense, the buyout formula, notice period, right of first refusal on the other's share.

The Dutch Supreme Court was explicit in 2023: without a samenlevingscontract, an unmarried partner has no automatic compensation right from the eenvoudige gemeenschap alone. The document creates the right; silence creates nothing.

The one practice that prevents most disputes

Every breakup buyout we've seen unravels at the same point: who actually paid what? Mortgage statements show the joint account; they don't show who funded it. Renovation receipts are in one partner's name; the cash came from the other. Three years in, no one remembers. Five years in, the figures get reconstructed under pressure — and the version that survives is usually the one of whoever kept the better records.

Two ledgers are non-negotiable from day one: every transfer in or out of the shared house account with who funded it, and every receipt for every shared cost — deposit, notary or conveyancing fees, taxes, repairs, appliances, the new boiler four years later. That ledger is what a court will ask for, what a buyout calculation needs, and what every cohabitation agreement will point to as the source of truth.

This is what CasaTab was built for — a multi-user household tracker where every expense is tagged to the person who paid it, so the answer to "who paid what" is never reconstructed from memory. You can track shared house costs in CasaTab from the moment the offer is accepted, alongside both partners on the same account.

The takeaway

Joint ownership is one of those decisions where the legal default is rarely what you actually want, and the paperwork that protects you costs less than dinner-for-two. Pick the mode that matches your contribution reality, write the will and the cohabitation agreement, and keep one contemporaneous ledger of every shared euro from the moment you sign. The relationship doesn't have to last forever for the documentation to be worth it — that's exactly when documentation pays.