Mortgages Explained

The anatomy of a mortgage

Capital: the amount you borrow.
Term: how long you take to repay — typically 25 years, increasingly 30–40. Longer terms mean lower monthly payments but far more total interest.
Loan-to-value (LTV): the loan as a percentage of the property's value. A £180k loan on a £200k home is 90% LTV. Lower LTV bands unlock cheaper rates — which is why deposit size matters so much.
Repayment vs interest-only: repayment mortgages clear the debt over the term; interest-only payments cover only interest, leaving the full capital due at the end — lenders require a credible repayment plan.

Rate types

Type	How it works	The trade-off
Fixed	Rate locked for 2, 3, 5 or 10 years	Certainty; but early repayment charges if you leave during the fix, and you won't benefit if rates fall
Tracker	Moves with the Bank of England base rate plus a margin	Cheaper when rates fall; payments rise when they rise
Standard variable rate (SVR)	The lender's default rate after a deal ends	Usually the most expensive place to sit — drifting onto SVR is the most common silent money leak in UK households

Run your own numbers

The mortgage repayment calculator shows monthly payments, total interest over the term, and what regular overpayments could change — every assumption stated.

What lenders actually assess

Income and affordability: not just salary multiples — lenders stress-test whether you could still pay if rates rose.
Outgoings and debts: childcare, loans, car finance and spending patterns all reduce borrowing capacity.
Credit history: missed payments, defaults and even unused credit limits shape both approval and rate.
Deposit/LTV: the band you land in (95%, 90%, 85%, 75%, 60%) often matters more than small rate differences between lenders.

Costs beyond the rate

Compare deals on total cost over the deal period, not headline rate alone: arrangement fees (often £999–£1,999, sometimes added to the loan — where they accrue interest for decades), valuation and legal fees, and early repayment charges. A lower rate with a big fee can cost more than a higher rate without one, especially on smaller loans.

Where advice fits

Most UK mortgage sales are advised — a broker or lender adviser must recommend a suitable deal. Mortgage brokers can be paid by commission from lenders, fees from you, or both; they must disclose which, and whether they search the whole market or a panel. The questions in our adviser-vetting toolkit apply to mortgage brokers exactly as they do to financial advisers — and every broker should appear on the FCA Register.

The remortgage countdown

The single most expensive default in UK personal finance is drifting onto the SVR when a fix ends. The fix for the fix:

Six months out: diarise it. Check your current balance, what your property is plausibly worth now, and therefore your new LTV band — you may have crossed into a cheaper one.
Three to six months out: mortgage offers typically last around six months, so you can lock a new deal early as insurance and still switch to something cheaper if rates fall before completion.
Compare two routes: a product transfer (new deal, same lender — fast, minimal checks, sometimes lazy pricing) versus a full remortgage to another lender (more paperwork, often better rates, fees to weigh). Brokers can price both.
Do the fee maths on the deal period, not the headline rate — the repayment calculator helps translate rates into pounds.

First-time buyers: help that actually exists

Lifetime ISA: a 25% government bonus on up to £4,000 a year towards a first home up to £450,000 — the rules and the penalty trap are in our Lifetime ISA guide.
95% LTV deals and the mortgage guarantee scheme: small-deposit lending exists; expect the priciest rate band and stress-tested affordability.
Shared ownership: buy a share, pay rent on the rest — genuinely helpful in expensive areas, with caveats worth understanding (rent + service charges on top of the mortgage, staircasing costs, resale restrictions).
Gifted deposits: common and accepted by most lenders, with paperwork confirming it's a gift, not a loan — and see the seven-year gift rule for the giver's side.

Common questions

Should I overpay my mortgage or invest instead?

A genuine it-depends: overpaying gives a guaranteed "return" equal to your mortgage rate, investing offers higher potential returns with risk. The answer turns on your rate, risk tolerance, tax position and timeline — a personal-recommendation question for an authorised adviser. Our overpay vs invest calculator shows both sides of the ledger on your numbers.

What happens when my fixed deal ends?

You move to the lender's SVR unless you act. Most people remortgage (with the same or a new lender) in the months before the fix ends — diarise it six months out.

Is my mortgage covered by the Ombudsman?

Residential mortgage lending and advice are FCA-regulated, so complaints about authorised lenders and brokers can go to the Financial Ombudsman Service.

How much can I borrow for a mortgage?

Rules of thumb say 4 to 4.5 times income, but lenders actually run affordability models: income minus committed outgoings, stress-tested at higher rates, adjusted for dependants, debts and even salary sacrifice arrangements. Two households with identical salaries can be offered very different sums — which is one genuine argument for a whole-of-market broker.

Sources and further reading

MoneyHelper — mortgages · FCA — mortgage information for consumers · GOV.UK — support for mortgage interest

About this guide: general education only — not regulated advice, not a personal recommendation, and not a financial promotion of any lender or product. Your home may be repossessed if you do not keep up repayments on a mortgage. FinancialAdvisor.co.uk is not an FCA-authorised firm.