Affordability and deposit — mortgage guides

How much you can borrow and why lenders arrive at that figure: income multiples, debt-to-income, stress tests, deposit size and the LTV bands that set your rate.

Mortgage basics Rates and costs Affordability and deposit Mortgage types Refinancing and overpaying

3 guides

A balance scale with everyday bills on one side

Debt to Income: The Ratio That Decides More Applications Than Salary

How DTI is calculated, what counts as debt, the caps that apply in different markets, and the fastest ways to move the ratio before applying.

Affordability and deposit 8 min read

Coins stacked in bands — each band buys a better rate

Deposit and LTV: Why the Bands Matter More Than the Amount

Rates are priced in LTV bands, so a small extra deposit that crosses a threshold can be worth more than any negotiation. Here is where the thresholds sit.

Affordability and deposit 9 min read

A tape measure across a doorway — the lender is measuring you, not the house

How Much Can I Borrow? What the Lender Is Actually Calculating

Income multiples are the rule of thumb; debt-to-income, the stress test and your outgoings are what really set the number. Here is the whole calculation.

Affordability and deposit 9 min read

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Last updated 2026-08-07 by mortgagecalculator.siten.co · About us

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