Before you start (mistakes 1–4)
Mistake 1: Applying to your bank first "because they know you"
Your bank sees your salary and current account activity — that's the extent of their advantage. They don't offer better rates because you've banked with them for 10 years. In fact, they typically only offer their own products (2–8 rates) versus a broker's 90+ lenders. Every FTB should get at least three product quotes: your bank, one comparison-site sourced product, and one broker recommendation.
Mistake 2: Racking up hard credit searches
Every full mortgage application triggers a hard credit search. Three or more hard searches in a 90-day window signals financial distress to automated scorecards and can trigger declines. Soft searches (for Mortgages in Principle at Nationwide, Halifax, most Building Societies) don't leave a visible footprint. Ask before agreeing to any credit check whether it's soft or hard.
Mistake 3: Making big life changes just before applying
Do not, in the 6 months before your mortgage application:
- Change jobs (unless it's a big pay rise you can evidence).
- Go self-employed.
- Take a car finance or personal loan.
- Start using Buy Now Pay Later regularly.
- Get a new credit card and increase your credit limits substantially.
- Miss any regular payment — even £5 on a subscription.
Mistake 4: Underestimating your ongoing costs
The mortgage payment isn't your monthly housing cost. Add council tax (£120–£300), utilities (£150–£280), buildings insurance, life cover, service charge (flats — £100–£350), maintenance reserve (target 1% of value annually). Real total is usually 40%–70% above the mortgage payment alone. See our FTB costs guide.
During the search (mistakes 5–8)
Mistake 5: Buying to your maximum affordability
The lender's affordability figure is a ceiling — not a target. Borrowing 90%+ of maximum leaves no room for interest rate rises, career breaks, children, or a boiler that breaks in year one. Aim for 75%–85% of maximum. See our how much can I borrow guide.
Mistake 6: Ignoring service charges on flats
Flats come with service charges that can rise significantly — from £150/month at purchase to £280/month within 3 years is not unusual. Ask for the full service charge history (last 5 years) before making an offer. Ask about any planned major works (roof repairs, cladding remediation, lift replacement) — these can trigger one-off charges of £5,000–£40,000.
Mistake 7: Falling in love with the wrong property
Warning signs that most FTBs overlook:
- Cladding on the exterior of any post-1990 building — EWS1 form required for mortgage.
- Short lease (below 85 years remaining on a flat) — lease extension costs £5k–£30k.
- Ground rent doubling clauses (older leases).
- Japanese knotweed within 7 metres of the property boundary.
- Non-standard construction (concrete, timber-framed pre-1970, steel-framed) — mortgage lender restrictions.
- Flood zone 2 or 3 — insurance issues.
- Recent flying freehold, unregistered land, or ransom strip.
Mistake 8: Skipping a proper survey
The lender's valuation is not a survey — it's a mortgage risk assessment. Save £500 by skipping a Level 2 HomeBuyer report and you may miss subsidence, dampness, roof failure, electrical hazards, and plumbing on the cusp of failure. A £550 survey has paid for itself many times over.
After the offer (mistakes 9–12)
Mistake 9: Choosing conveyancer on price alone
The £400 conveyancer will take twice as long as the £900 one, miss critical enquiries, and leak fees at every step. Choose a fixed-fee conveyancer with strong Google reviews and clear communication. Reject any who won't quote fixed fees upfront.
Mistake 10: Not asking the right seller enquiries
Beyond the standard TA6 form, ask your conveyancer to formally raise:
- Any building work done without planning permission or building regulations sign-off.
- Boundary disputes with neighbours.
- Notices from the local authority in the last 10 years.
- Insurance claims on the property in the last 5 years.
- For flats: the last 3 years of service charge accounts and reserve fund position.
Mistake 11: Accepting the estate agent's mortgage referral
Estate agents refer mortgage business to in-house brokers who pay them referral fees (£300–£600 per completed mortgage). These brokers are legally regulated and often perfectly competent — but they have a commercial reason to prefer certain lenders. Get an independent broker quote for comparison.
Mistake 12: Buying furniture and gadgets between exchange and completion
Between exchange and completion (typically 1–4 weeks), your lender re-runs a credit check. New credit taken in that window — a £4,000 sofa on finance, a £2,000 Klarna order for kitchenware — can void your mortgage offer. Wait until you have the keys before opening any new credit.
After completion (mistakes 13–15)
Mistake 13: Auto-renewing the lender's insurance
Your lender may sell you buildings insurance for £320/year. The same cover from a comparison site typically costs £180–£220/year. Never accept the auto-quote — shop each renewal.
Mistake 14: Rolling onto the SVR at end of fix
At the end of your 2 or 5-year fixed rate, your lender's Standard Variable Rate (SVR) — typically 7%–9% in 2026 — kicks in automatically. On a £200k mortgage, that's £300–£500/month extra. Set a calendar reminder 6 months before your fix ends and remortgage or product-transfer.
Mistake 15: Not overpaying in year one
Most FTB fixed rates allow 10% annual overpayments penalty-free. Overpaying £200/month from month one of a £200k mortgage saves ~£35,000 in interest over 30 years and cuts the term by nearly 6 years. It's the highest-return use of surplus cash most FTBs will ever have.
Frequently asked questions
Related guides
First-Time Buyer Guide UK
Complete step-by-step FTB journey.
Read guideFirst-Time Buyer Costs
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Read guideFTB Conveyancing Guide
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Read guideFirst-Time Buyer Deposit
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Read guideQuestions to Ask a Broker
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