If your child is struggling to buy a home in 2025, you are not alone. Average deposits in England now sit north of £50,000, and in London the figure is closer to £130,000. The so-called “Bank of Mum and Dad” has become one of the largest de facto mortgage lenders in the country — yet it operates with almost no legal structure, minimal tax planning, and a worrying assumption that family goodwill will prevent disputes. It won’t always. This guide sets out what every parent (and child) needs to know before a single pound changes hands.
Gift or Loan? Get This Wrong and Everything Else Falls Apart
The first question your solicitor, your child’s mortgage lender, and — eventually — HMRC will ask is whether the money is a gift or a loan. These are not interchangeable labels you can swap to suit the moment. A gift means you surrender all legal and beneficial interest in the funds permanently. A loan means you expect repayment, and you retain an enforceable right to recover the money. Mortgage lenders care intensely about the distinction because an outstanding loan is a liability on your child’s affordability assessment. Most high-street lenders will insist parents sign a “gifted deposit declaration” confirming the money is an outright gift with no expectation of repayment. Once you sign that declaration, you will find it extraordinarily difficult to later argue in court that the money was really a loan.
If you genuinely intend a loan, you need a formal written loan agreement — ideally executed as a deed, which carries a twelve-year limitation period for enforcement rather than six years for a simple contract. The agreement should specify the principal amount, interest rate (even if zero), repayment schedule, what happens on default, and whether the loan is secured against the property. A loan that sits on paper but is never repaid looks like a sham to a court and to HMRC. Actual repayments must happen, and they should be traceable through bank statements.
Inheritance Tax: The Seven-Year Clock and Its Traps
If you make an outright gift and survive seven years, it falls outside your estate for Inheritance Tax (IHT) purposes. Die within seven years and the gift is a “potentially exempt transfer” (PET) that gets clawed back into your estate, with taper relief only applying after the third year. Most parents understand this much. What they miss is the gift with reservation of benefit rule. If you gift your child money for a deposit but then move into the property rent-free, HMRC will treat the property (or your share of it) as remaining in your estate regardless of how many years pass. You must either pay a full market rent or stay well away from the asset to avoid this trap.
There is also the annual gift exemption of £3,000 per tax year (and you can carry forward one unused year), plus the small gifts allowance of £250 per recipient. These are modest sums against today’s deposit requirements, but they are worth using methodically as part of a longer-term gifting strategy. For parents with larger estates, the cumulative total of lifetime gifts above the nil-rate band (currently £325,000) will determine any IHT liability on death.
Stamp Duty Land Tax: The Surcharge That Catches Everyone Off Guard
Here is a scenario that destroys financial plans at the point of completion. Your child is a first-time buyer and qualifies for SDLT relief on properties up to £425,000. You decide to go on the title as a joint owner to “protect your investment.” If you already own any residential property — anywhere in the world, including a buy-to-let, a holiday cottage, or a share in a property abroad — the 3% SDLT higher rate surcharge applies to the entire purchase price. Your child’s first-time buyer relief vanishes completely. On a £400,000 property, that surcharge alone would be £12,000. The lesson is blunt: think very carefully before putting a parent’s name on the legal title.
Joint and Several Liability: The Risk No One Explains Properly
If you do go on the mortgage, you are jointly and severally liable for the entire debt — not half, not your “share,” but one hundred per cent. If your child stops paying, the lender will pursue you for the full outstanding balance. Equally important: that mortgage will appear on your credit file and will be stress-tested against your income in any future borrowing application. If you plan to remortgage your own home, take out equity release, or help another child buy, the existing joint mortgage may scupper your capacity entirely.
Tenancy in Common, Not Joint Tenancy
If parents and children do co-own a property, it should almost always be held as tenants in common rather than joint tenants. Joint tenancy carries a right of survivorship — when one owner dies, their share passes automatically to the surviving owner regardless of what any will says. That may sound convenient, but it means a parent’s share bypasses their estate, potentially disinheriting other children or disrupting IHT planning. Tenancy in common allows each party to hold a specified percentage, leave their share to whomever they choose, and — crucially — reflect unequal financial contributions accurately.
The Declaration of Trust: Non-Negotiable
A Declaration of Trust (also called a Deed of Trust) is the single most important document in any Bank of Mum and Dad arrangement where parents retain a beneficial interest. Without one, the default legal presumption for joint owners is equal shares — regardless of who actually put in the money. The declaration should set out:
- Each party’s beneficial interest as a percentage.
- Whether unequal contributions are treated as loans or equity stakes.
- What happens on sale: distribution waterfall, priority of repayments.
- A right of first refusal mechanism if one party wants to sell and the other does not.
- An exit timeline — how long the non-selling party has to arrange a buyout.
- Rules on occupancy, shared expenses, renovation consent thresholds, and subletting.
Have it executed as a deed. Register a restriction at the Land Registry so the property cannot be sold or remortgaged without the trust terms being satisfied. This is not optional paperwork — it is the difference between an orderly exit and a courtroom.
TOLATA: When Family Disagreements Become Litigation
Under the Trusts of Land and Appointment of Trustees Act 1996 (TOLATA), any co-owner can apply to court to force a sale of jointly owned property, even if the other owner objects. The court will consider factors including the purpose for which the property was bought, the welfare of any minor children in occupation, and the interests of any secured creditor. TOLATA claims are expensive, slow, and emotionally devastating. They are also far more common than most families imagine — particularly when a child’s relationship breaks down and a partner or ex-spouse enters the picture. A properly drafted Declaration of Trust can include dispute resolution clauses (mediation before litigation) and pre-agreed sale triggers that reduce TOLATA exposure significantly.
Capital Gains Tax and Principal Private Residence Relief
If a parent holds a beneficial interest in a child’s property but does not live there, they cannot claim Principal Private Residence (PPR) relief on their share. When the property is sold at a profit, the parent’s portion of the gain is subject to Capital Gains Tax at 18% (basic rate) or 24% (higher rate) after the annual exempt amount. Parents who already own their own home and hold a share in a child’s property effectively have two residential interests — and PPR can only cover one main residence at a time. This is a planning point that gets overlooked until the tax bill arrives.
Practical Steps: What to Do Before You Transfer Any Money
- Decide gift or loan — and mean it. Do not sign a gifted deposit declaration if you expect repayment.
- Instruct a solicitor independently. Your child’s conveyancer acts for your child. You need separate legal advice.
- Execute a Declaration of Trust as a deed if you retain any beneficial interest, and register a restriction at the Land Registry.
- Keep meticulous records: bank transfers, agreements, repayment schedules, correspondence. Courts decide disputes on evidence, not recollections.
- Review your will and IHT position. A large gift may push your estate above or below critical thresholds, and your will should reflect the new asset structure.
- Check the SDLT position before anyone’s name goes on the title. Get a written calculation from the conveyancer at instruction stage, not at exchange.
- Talk to your other children. Unequal gifts breed resentment. If you intend to equalise later through your will, document that intention clearly.
The Bank of Mum and Dad is an act of extraordinary generosity — but generosity without structure is just risk. Take the time, spend the money on proper legal advice, and treat this transaction with the seriousness it deserves. Your family relationships, your retirement security, and your child’s financial future all depend on getting it right from the start.
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.
