Quick Answer
A Decision in Principle (DIP) is a statement from a lender showing how much they may be willing to lend you for a mortgage, based on an initial assessment of your finances. It is not a guaranteed offer, but it gives you a strong indication of your borrowing power.
What Does a Decision in Principle Mean?
A DIP (also called an Agreement in Principle) is an early step in the mortgage process.
It tells you:
- How much you may be able to borrow
- Whether a lender is likely to approve you
- That you are a serious buyer
Estate agents often ask for a DIP before accepting an offer on a property.
How Does a DIP Work?
When you apply for a DIP, the lender will carry out a basic check of your finances.
This usually includes:
- Your income
- Your employment status
- Your existing debts
- A credit check (soft or sometimes hard)
Based on this, they give an estimate of how much you can borrow.
Is a DIP a Guaranteed Mortgage?
No — a DIP is not a formal mortgage offer.
It is only an indication.
Your application can still be declined later if:
- Your full financial checks raise concerns
- Your circumstances change
- The property does not meet lender criteria
For more on this, see our guide:
What Will Get You Declined for a Mortgage UK
Does a DIP Affect Your Credit Score?
Usually, a DIP involves a soft credit check, which does not affect your credit score.
However:
- Some lenders may perform a hard check
- Multiple applications in a short time can have an impact
It’s best to limit applications and use a broker if unsure.
How Long Does a DIP Last?
A typical DIP is valid for:
👉 60 to 90 days
After this period, you may need to reapply if you have not yet found a property.
How Much Can You Borrow with a DIP?
The amount offered in a DIP is based on affordability.
Most lenders use:
👉 4 to 4.5 times your income
However, this can vary depending on:
- Your expenses
- Existing debts
- Deposit size
- Credit history
To get a clearer picture, use our
Mortgage & Cost Calculators UK (2026) page.
When Should You Get a DIP?
You should consider getting a DIP:
- Before viewing properties
- Before making an offer
- To understand your budget
Having a DIP makes you a more attractive buyer.
What Do You Need to Apply for a DIP?
Most lenders will ask for basic details, such as:
- Income and employment information
- Monthly expenses
- Outstanding debts
- Personal details
You usually won’t need full documentation at this stage.
What Happens After a DIP?
Once you’ve found a property:
- You submit a full mortgage application
- Provide detailed documents (payslips, bank statements)
- The lender carries out full checks
- A formal mortgage offer is issued (if approved)
What Can Go Wrong After a DIP?
Even with a DIP, your application can still fail.
Common reasons include:
- Changes in income or employment
- Increased spending or new debts
- Issues with the property
- Failing affordability checks
Check Your Budget Before Applying
A DIP is useful, but it’s only part of the picture.
Before applying, you should understand your true monthly costs, including:
- Mortgage payments
- Bills
- Food and transport
- Lifestyle spending
👉 Use our Mortgage & Cost Calculators UK (2026) to plan your budget properly
Related Guides
- How Much Can I Borrow for a Mortgage UK
- What Will Get You Declined for a Mortgage UK
- Mortgage Fees UK
- Fixed vs Tracker Mortgage UK
Final Thoughts
A Decision in Principle is a valuable first step when buying a home.
It gives you confidence, shows sellers you are serious, and helps you understand your borrowing potential — but it’s not a guarantee, so proper financial preparation is essential.