Family Mortgage Loan: Rules, Risks & Gift Letters

By The Chipkie Team, Personal Finance Editorial Team  ·  Last updated 25 August 2026

With average two-year fixed rates still biting and lenders stress-testing affordability harder than most first-time buyers expect, more UK families are asking a blunt question: why pay a bank at all? A properly structured family mortgage loan — parents lending the capital directly, secured against the property — can cut a generation’s worth of interest out of a house purchase. Done casually, over a WhatsApp message and a bank transfer, it does the opposite: it creates an unsecured, unprovable claim, muddles your inheritance tax position, and can quietly turn into mortgage fraud if the money is really meant for a deposit behind a high-street loan.

The difference between those two outcomes is paperwork. This guide sets out how to do it properly under UK law in 2026.

Key Takeaways

• A family mortgage should be documented as a deed and secured by a legal charge registered against the property title at HM Land Registry — otherwise the lending parent has no enforceable claim on the house.
• Obligations in a deed carry a 12-year limitation period under the Limitation Act 1980, compared with six years for an ordinary written contract.
• The UK has no gift tax and no equivalent of the US Applicable Federal Rate — you are free to set the rate, but any interest you receive is taxable savings income.
• HMRC’s inheritance tax nil-rate band is £325,000 and remains frozen; an outstanding family loan stays an asset of the lender’s estate, while a released debt is treated as a gift subject to the seven-year rule.
• If the money is going toward a deposit behind a bank mortgage, a loan is rarely an acceptable source of funds — and signing a gifted deposit letter while expecting repayment is fraud under the Fraud Act 2006.

What does it actually mean for parents to act as the mortgage lender?

It means replacing the bank entirely: the parents advance the purchase money, the child owns the property, and the parents hold a legal charge over that property as security. The child repays them on an agreed schedule. Legally it is a loan secured on land — a real mortgage, just with a different lender on the other side of the table.

That is a fundamentally different arrangement from the two things families usually do instead:

• An outright gift — money handed over with no repayment expected, which starts the inheritance tax clock and gives the parents no claim if the marriage or the relationship breaks down.
• A “soft loan” — an informal handshake with no security, which ranks behind every other creditor and is frequently unprovable.
• Joint ownership — parents on the title and the mortgage, which triggers joint and several liability and the Stamp Duty Land Tax higher rate on the whole purchase price if the parent already owns a home anywhere in the world.

One regulatory point most articles miss. Entering into a regulated mortgage contract as lender is a regulated activity — but only where it is carried on by way of business. A genuine one-off loan to your own child is not normally lending by way of business, which is why the “Bank of Mum and Dad” secured loan is workable at all. If you are lending repeatedly, to multiple people, or at commercial rates, take advice: the Financial Conduct Authority perimeter is not something to guess at.

How do you set up a family mortgage so it is actually enforceable?

Execute the loan as a deed, then register a legal charge against the title at HM Land Registry through a conveyancing solicitor. Service the loan like a bank would — fixed monthly payments by standing order, a written amortisation schedule, and an annual balance statement. Undocumented, unsecured family money is treated by courts and HMRC as whatever the evidence says it is, which is usually nothing helpful.

1. Agree the commercial terms first: amount, interest rate, term, repayment or interest-only, what happens on early repayment, sale, death or default.
2. Have the agreement drafted and executed as a deed. This matters: under the Limitation Act 1980 a deed gives you 12 years to enforce, against six for a simple contract. On a 25-year loan, that gap is not academic.
3. Instruct a solicitor to create and register the legal charge. Recording a deed of trust or charge is what converts a promise into a proprietary right. Registration fees are set by HM Land Registry and change periodically — check the current scale before you budget.
4. Set up the servicing. Standing order from the borrower’s account, on the same date each month, with a reference. Our experience across the agreements our users create is that payment trails, not intentions, decide disputes.
5. Add a declaration of trust if anyone else is contributing — a partner, a sibling, a second parent. Without one, courts and HMRC default to equal beneficial shares regardless of who actually paid.

If you want the mechanics of the document itself, our guide to writing a family loan agreement under UK law walks through each clause.

How does a family mortgage compare with a bank mortgage on cost?

A family mortgage removes lender arrangement, broker and valuation fees, but not the legal and registration costs of taking security. You save the lender’s margin, not the conveyancing. Budget for solicitor fees on both sides, Land Registry registration of the charge, and independent legal advice for the borrower.

Can family money be used as a deposit behind a high-street mortgage?

Only if it is a genuine gift. UK lenders almost universally require a gifted deposit letter confirming the money is a gift, is non-repayable, and that the giver retains no interest in the property. A family loan is not an acceptable deposit source for most lenders and will be refused outright once disclosed. Undisclosed borrowed deposits are treated as fraud.

This is the single most dangerous crossover in the whole topic. If your child is buying with a bank mortgage and your money is funding the deposit, you cannot have both: you cannot take a charge over the property and sign a letter saying you retain no interest in it.

A gifted deposit letter becomes a false representation the moment any of the following is true:

• Repayment is expected, in whole or in part, on any timescale.
• There is a side agreement, verbal or written, that the money comes back on sale.
• The giver expects a share of the equity or the sale proceeds.
• The “gift” is contingent on the borrower doing something in return.

Making a false representation to obtain a mortgage advance is fraud under section 2 of the Fraud Act 2006, which carries a maximum sentence of 10 years’ imprisonment on indictment. In practice, lenders also demand immediate repayment of the whole loan and report the matter to the National Fraud Database. Solicitors are obliged to report what they see. If you want the money back, structure it as a declared loan or a documented equity share and accept that the borrowing capacity will fall — or read our note on family help for first-time buyers before you commit to anything.

What are the tax and inheritance consequences in the UK?

There is no UK gift tax and no statutory minimum interest rate for family lending. Interest you charge is taxable savings income, declarable through Self Assessment. An outstanding loan balance remains an asset of your estate for inheritance tax. Releasing the debt is a gift, subject to the seven-year rule.

Key points, using current HMRC figures:

• Annual gift exemption: £3,000 per tax year, with one unused prior year available to carry forward — up to £6,000.
• Small gifts: £250 per recipient per tax year, to any number of people, provided no other exemption is used for that person.
• Nil-rate band: £325,000 and frozen, with an additional residence nil-rate band where a home passes to direct descendants.
• Seven-year rule: gifts are potentially exempt transfers. Survive seven years and they fall out of the estate. Taper relief between three and seven years reduces the tax due, not the value of the gift — a distinction people get wrong constantly.

Two things families overlook. First, if you charge interest below what you could earn elsewhere, that forgone interest is not itself a taxable gift — but the loan sitting on your balance sheet is still an estate asset at full face value. Second, if your will forgives the loan, the executors must still account for it. Check the current position on HMRC’s personal tax pages and take advice on rates and allowances that are not fixed year to year. MoneyHelper has free, impartial guidance on family lending and estate planning.

What happens if a family mortgage borrower stops paying?

If you hold a registered legal charge, you have the enforcement powers of a mortgagee under the Law of Property Act 1925, including possession and sale — though a court order is required for a residential property. Without a charge, you are an unsecured creditor pursuing a personal debt, ranking behind every secured lender.

Can a family loan sit behind a bank mortgage as a second charge?

Sometimes, but only with the first-charge lender’s written consent, and most mainstream lenders refuse it where the second charge funds the deposit. A second charge ranks behind the bank: in a forced sale, the bank is paid in full before you see anything. Never register one without telling the primary lender.

Do I need to charge interest on a family mortgage?

No. UK law imposes no minimum rate, and there is no Applicable Federal Rate concept here — that is a US mechanism with no UK equivalent. Charging nothing is perfectly lawful. If you do charge, the interest is taxable savings income for you and must be declared. Our guide on setting a fair family loan interest rate covers the trade-offs.

What if my child separates from their partner after we lend?

A registered charge survives a relationship breakdown; an informal loan usually does not. Courts routinely reclassify undocumented parental money as a gift where there is no written agreement, particularly in divorce proceedings. A deed plus a declaration of trust recording beneficial shares is the only reliable protection.

Where should you start?

Decide first whether you are lending or giving, and never blur the two. If you are lending, treat it as a real mortgage: a deed, a registered charge, a schedule, and payment records. If you are giving, say so honestly and in writing, and accept that the money is gone. Everything expensive that happens to families in this area happens in the grey area between those two positions.

Get the paperwork right from day one — you can create a clear, legally structured family loan agreement in minutes with Chipkie, then take it to your conveyancer to have the charge registered. It is a fraction of the cost of the argument you avoid, and considerably cheaper than a bank.

Disclaimer: The information provided in this article is for informational purposes only and should not be considered financial or legal advice. Property and lending laws in the United Kingdom vary and may change over time. We always recommend consulting with a qualified solicitor and mortgage broker before entering into a property purchase or financial arrangement with another party.