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UK mortgage guide

Mortgage in principle vs full application: what is the difference?

· 5 min read

You will hear several mortgage terms when you start buying a home, and they are easy to mix up. A mortgage in principle, a full application and a mortgage offer are three different stages. Understanding them helps you know what to prepare and when.

Mortgage in principle

A mortgage in principle, sometimes called a decision in principle or agreement in principle, is an early indication of how much a lender might be willing to lend you. You give basic details about your income, outgoings and deposit, and the lender usually runs a credit check.

  • It is quick, often online.
  • It is not a promise to lend.
  • Estate agents often ask for one before accepting your offer.
  • It usually lasts for a limited time, such as 30 to 90 days.

Full mortgage application

A full application happens once you have found a property and had an offer accepted. The lender checks your documents in detail, verifies your identity, income and deposit, and arranges a valuation of the property.

  • You provide your full document set (ID, address, payslips or accounts, bank statements, deposit proof).
  • The lender carries out detailed affordability and credit checks.
  • A valuation is carried out on the property.

Mortgage offer

If the lender is satisfied with you and the property, it issues a formal mortgage offer. The offer will state the amount, rate, term and conditions, and usually has an expiry date. Your solicitor can then progress the purchase.

Which documents when

  1. Mortgage in principle: basic income, outgoings and deposit details, and sometimes ID.
  2. Full application: the complete document set.
  3. Offer: any outstanding items the lender asks for as conditions.

Frequently asked questions

Does a mortgage in principle affect my credit score?

Some lenders use a soft credit check and others a hard one. Ask which before you apply.

How long does a mortgage in principle last?

It depends on the lender, but it is often valid for around 30 to 90 days.

Do I need a mortgage in principle to make an offer?

Not legally, but many estate agents expect you to have one to show you are a serious buyer.

Sources and further reading

More mortgage guides

Documents you need for a UK mortgage application: the complete checklistA plain-English checklist of the documents UK lenders usually ask for: ID, proof of address, payslips, bank statements, deposit evidence and more, with tips to avoid delays.First-time buyer mortgage documents: what to prepare before you applyBuying your first home in the UK? Here are the documents lenders usually ask first-time buyers for, plus what to prepare for your mortgage in principle, deposit and solicitor.Self-employed mortgage documents: what lenders want to seeSelf-employed and need a UK mortgage? Learn which documents lenders usually ask for, including SA302s, tax year overviews, accounts and business bank statements.Remortgage documents checklist: what you need to switch your mortgagePlanning to remortgage in the UK? Here is the checklist of documents lenders typically ask for, from your current mortgage statement to payslips and bank statements.