What counts as a large mortgage?
There is no single definition, though most lenders treat any mortgage above £500,000 as large or high-value. Some draw the line higher, at £750,000 or £1 million. Above these figures the automated checks a lender normally runs may no longer apply, and a senior underwriter is more likely to look at your case by hand.
That label matters because how keen a lender is, what they ask for, and the rate they charge can all shift on a larger loan. Some high street lenders cap their maximum loan at £500,000 or £1 million. Private banks and specialist lenders, by contrast, handle cases of £2 million or more as a matter of routine.
Income requirements and affordability
Lenders looking at a large mortgage usually want to see a strong income or substantial assets behind it. The standard income multiple of 4 to 4.5 times salary often will not stretch far enough here, so some lenders raise it to 5 or even 6 times income for high earners and for professionals in certain fields.
Income at this level is often anything but simple. Lenders who know the large-mortgage market will take account of bonuses, commission, share options, dividend income, rental income, and money earned abroad. What makes the difference is presenting all of it in the form each lender is set up to accept.
Deposit and LTV considerations
For a high-value home, most lenders ask for a bigger deposit in percentage terms. Standard purchases can be done at 90% or 95% loan-to-value (the size of your loan set against the property’s value), but large mortgage lenders usually want at least a 20% to 25% deposit, and some will ask for more depending on the client.
The deposit also needs to come from somewhere the lender can trace. They will look for evidence of savings, money from a property sale, investments, or another legitimate origin. If part of the deposit is a gift, expect the usual gifted-deposit declarations and anti-money-laundering checks.
Why specialist advice matters
At this level, the gap between a good deal and an average one can be worth thousands of pounds a year in interest. A broker who handles large mortgages regularly knows which lenders price a big loan keenly, and which ones are willing to bend on criteria or turn a case around fast.
They can also help you set the borrowing up in the most tax-efficient way, whether you borrow in your own name, through a limited company, or through an offset arrangement that sets your savings against the loan to cut the interest you pay. Interest-only mortgages are common at this level too and worth weighing up. Getting the structure right at the outset can save a large amount over the years you hold the mortgage.