In short
If one partner contributes more, the deed can record unequal ownership shares matching what each paid, even though both remain fully liable to the lender for the whole mortgage. Without that express split, equal halves are presumed, and correcting it later costs money and tax.
Separate ownership from mortgage liability
When two people buy together, three questions must be distinguished: who contributes cash, who owns what share and who owes the mortgage.
The purchase deed records ownership. The loan determines obligations to the lender. A private understanding between the couple may not limit the bank’s rights.
Record every contribution
Document the source and amount of the reservation, deposit, taxes, completion funds and later capital repayments. Keep bank evidence and avoid unexplained transfers.
If one contribution is a gift or family loan, obtain tax and legal advice before completion. Informal arrangements can create later disputes or reporting consequences.
Decide the ownership structure before signing
The right percentages and agreements depend on marriage or partnership status, governing law, residence and future intentions. An independent lawyer or notary should advise on the deed and any separate agreement.
A mortgage broker can calculate affordability but should not decide the couple’s legal ownership structure.
Model future scenarios
Discuss sale, separation, early repayment, renovation contributions, death, inability to pay and one person wishing to keep the home. Decide how market gains, losses and outstanding debt would be handled.
The lender assesses both applicants
Where both borrow, the bank reviews each income, debt and credit profile and may impose joint liability. A larger deposit reduces the requested loan but does not by itself resolve a weak affordability case.
Build a shared transaction file
Combine the agreed price, ownership advice, cash contributions, mortgage amount and recurring payment plan. This prevents the financing process from silently deciding a legal question the couple has not addressed.
RCG Finance can prepare the mortgage comparison. Use a separate qualified adviser for ownership, family-law and tax decisions. Request a financing review once the intended structure is clear.
Sources and review
Prepared by the RCG Finance editorial team (RCG 2026 S.L., Bank of Spain register of credit intermediaries no. E760) and reviewed by Rafael, founder of RCG Finance and former debt and M&A advisor at KPMG and PwC, under our editorial standards. Last source review: 8 September 2026.
Frequently asked questions
Does paying more deposit automatically create a larger ownership share?
Do not assume so. Ownership follows the deed and applicable law; contributions and reimbursement claims need specific legal advice and documentation.
