What is a mortgage Agreement in Principle (AIP)?
An Agreement in Principle (also called Decision in Principle) is a lender's conditional commitment to lend you a certain amount. It's based on a credit check and your stated income, typically valid for 60-90 days.
An AIP shows estate agents and sellers that a lender has assessed your finances and is willing to lend you a specific amount in principle. It strengthens your position when making offers on properties. Getting an AIP involves providing income details, employment information, and undergoing a credit check (some lenders use soft checks that don't affect your score). The AIP isn't a guarantee - you'll still need to complete a full mortgage application - but it shows you're a credible buyer who can likely secure finance.
Key Points
- 1Shows how much a lender may offer
- 2Usually valid for 60-90 days
- 3Not a guarantee - full application still needed
- 4Some use soft credit checks (no score impact)
- 5Strengthens your position with estate agents
Next Steps
- 1Gather income and employment details
- 2Check your credit report first
- 3Apply online or through a broker
- 4Use your AIP when viewing properties
- 5Progress to full application when offer accepted
Why This Matters for Your Mortgage
Understanding these details helps you make informed decisions during the mortgage process. Every element of your application—from deposits to documentation—affects your approval chances and the rates you can access.
Lenders assess applications holistically, weighing multiple factors together. Knowing what they look for allows you to present the strongest possible application. This is particularly important for non-standard situations where lender criteria varies significantly.
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Related Questions
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First-Time Buyers
Content reviewed: January 2026
CeMAP awarded by The London Institute of Banking & Finance. Cert CII (MP) awarded by the Chartered Insurance Institute.