Large Loan Mortgage FAQ
General information only. This is not financial advice.
Last reviewed: 2026-06-06
What counts as a large loan mortgage in the UK?
There is no universal definition, but most specialist lenders and private banks treat mortgages above £500,000 to £1 million as large loans requiring additional scrutiny. Above £1 million, bespoke or private banking underwriting is almost always required. At these levels, standard affordability calculators are often set aside in favour of a holistic assessment of the borrower's overall financial position, asset base, and income complexity.
How do lenders assess affordability for large loan mortgages?
Large loan lenders typically look beyond a simple income multiple. They consider net worth, liquid assets, investment portfolios, and the overall balance sheet alongside declared income. Stress testing is applied to ensure repayments remain sustainable if interest rates rise significantly. For borrowers with complex income — such as company directors, equity partners, or those receiving carried interest — underwriters will conduct a manual review rather than relying on automated scoring.
What deposit do I need for a large loan mortgage?
Most large loan lenders require a minimum 25% deposit, and many prefer 40% or more at higher loan sizes. Above £2 million, it is common for lenders to require at least 35–40% equity, partly because resale liquidity for high-value properties can be lower and partly because lenders seek to limit their exposure on a single asset. A strong overall financial profile — substantial assets, diversified income — can sometimes support a higher loan-to-value at the lender's discretion.
Do private banks offer better terms for large mortgage borrowing?
Private banks can be more flexible than mainstream lenders when assessing complex income and overall wealth, and they sometimes offer competitive rates for borrowers who hold or move significant assets under management with them. However, the expectation of a broader banking relationship — including investment accounts or wealth management mandates — is common. Private bank mortgages are also assessed individually rather than through automated systems, which can work in favour of high-net-worth borrowers whose income does not fit standard templates.
Are large loan mortgages stress-tested differently?
The FCA's mortgage affordability rules apply to regulated residential mortgages regardless of loan size, but large loan lenders typically apply their own internal stress tests on top of the regulatory minimum. It is common for lenders to stress the rate at 2–3 percentage points above the initial pay rate and to model scenarios such as a reduction in bonuses or investment income. Some private banks will also consider the borrower's broader asset base as a secondary means of support, giving more comfort at higher loan sizes.
What income evidence do large loan lenders typically require?
Evidence requirements at large loan sizes are generally more comprehensive than for standard mortgages. Salaried borrowers typically need three months' payslips, a P60, and an employer's reference for bonuses or commission. Self-employed borrowers and directors will usually need three years of accounts and SA302s, though some lenders will consider two years if supplemented by a strong asset position. Lenders may also request professional references, accountant letters, or evidence of investment income and asset holdings — especially where income comes from multiple or variable sources.
Risk warning
Your home may be repossessed if you do not keep up repayments on your mortgage. Think carefully before securing other debts against your home. This article is general information only and does not constitute financial advice.
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