How getting a mortgage works, from AIP to offer
The short answer
Four stages: an agreement in principle (minutes to a day, soft credit check), the full application once an offer's accepted (documents and a hard check), the lender's valuation of the property, then the formal mortgage offer - typically two to six weeks after applying. The offer usually lasts six months, and your conveyancer needs it before exchange.
The four stages
- 1
Agreement in principle (before house-hunting)
A lender or broker checks income, outgoings and a soft credit search, and states what you could likely borrow. Not binding either way - but agents and sellers take offers with an AIP far more seriously, and it surfaces credit surprises while they're still fixable.
- 2
Full application (offer accepted)
The real thing: payslips or accounts, bank statements, ID, deposit evidence, and a hard credit check. Underwriters may query spending patterns or ask for more paper - normal, answer fast, and change nothing about your finances mid-flight.
- 3
Valuation
The lender confirms the property is worth lending against. Often desk-based or drive-by; it protects the bank, not you - the case for your own survey is separate and covered in our survey guides.
- 4
Offer (2-6 weeks from application)
The formal offer goes to you and your conveyancer, with conditions to satisfy before completion. Offers typically last six months - enough for most chains, extendable with most lenders if yours crawls.
Where the time goes, and how to spend less of it
The AIP is fast. What stretches applications: missing documents (have three months of payslips and statements, or two years of accounts if self-employed, ready before you apply), valuation booking backlogs at busy lenders, and underwriter queries answered slowly. A broker earns their keep here as much as at product choice - they know each lender's current service speeds and chase inside channels you don't have. What a broker costs, and how they're paid, is covered in the broker fees guide; how much the resulting rate matters is one slider-drag in the mortgage calculator.
Want the application run for you?
Verified whole-of-market brokers handle the paperwork and chase the lender - free consultations, no obligation, no credit-file marks at this stage.
Compare mortgage brokersCommon questions
How long does an AIP take and how long does it last?
Minutes online, a day via some brokers; typically valid 30 to 90 days. Refreshing one is trivial, so get it before viewings rather than during negotiations.
Does an AIP guarantee I'll get the mortgage?
No - it's a screened estimate, not underwriting. Full application can still fail on documents, valuation or deeper credit checks, which is why nobody sensible exchanges contracts before the formal offer exists.
What if the valuation comes in below my offer?
A down-valuation caps what the lender advances. Options: renegotiate the price with evidence, find more deposit, or try a lender whose valuers read the local market differently - the classic broker rescue job.
When in the buying process should I start?
AIP before serious house-hunting; full application the day your offer is accepted. Mortgage and conveyancing run in parallel - the offer is usually the pacing item in a quick purchase, so start its clock first.
Sources and further reading