When it comes to buying a home, one of the simplest yet most powerful guidelines you can follow is the 30% Mortgage Rule. It says: Keep your monthly mortgage payment at no more than 30% of your total monthly income. For instance on a 100k a year salary that would mean a mortgage payment of up to 2.5k a month.
As a mortgage broker, it’s not just a number to me, it’s a strategy that protects your finances, improves your chances of mortgage approval, and sets you up for long‑term success in the housing market.
Protects Your Home and Family
By capping your mortgage at 30% of your income, you leave room in your budget for essential protection:
- Life insurance and critical illness cover to safeguard your family’s future.
- Income protection to keep payments covered if you can’t work.
- If the worst happens, you’ll have the financial resilience to keep your home
Keep You Looking at Property Within Budget
The 30% rule acts as a built‑in filter when house‑hunting:
- You avoid falling in love with homes that would stretch you too thin.
- You focus on properties you can comfortably afford, reducing the risk of financial stress later.
- You can still enjoy life outside your mortgage, with things like holidays, hobbies, and family time that don’t have to disappear.
Improves Your Chances of Passing Lender Affordability Checks
Mortgage lenders assess whether you can afford repayments now and in some instances, if rates rise in the future. If your mortgage is within 30% of your income:
- You’re more likely to pass affordability stress tests.
- You’ll have a buffer if interest rates increase.
- You present yourself as a lower‑risk borrower.
Gives You Healthy Exposure to the Housing Market
A mortgage at 30% of your income is big enough to:
- Build equity over time.
- Benefit from potential property price growth.
- Avoid over‑leveraging, which can be risky if the market dips.
It’s the sweet spot between participating in the market and protecting your financial stability.
Leaves Room for Savings and Investments
With only 30% of your income going to the mortgage:
- You can build an emergency fund for unexpected costs.
- You can invest in pensions, ISAs, or other assets for long‑term growth.
- You’re not forced to choose between paying the mortgage and saving for the future.
- This is your real wealth builder, and allows for it to be a priority
Reduces Stress and Increases Flexibility
Lower housing costs mean:
- You can handle income changes, such as starting a family or changing careers.
- You have more flexibility to overpay your mortgage if you want to become debt‑free sooner.
- You’re less likely to feel 'house poor' where most your money is tied up in your home.
Key Takeaways
- The 30% Mortgage Rule protects your ability to protect your home and family should the worst happen.
- Keeps your property search realistic and affordable.
- Improves your chances of passing lender affordability checks.
- Gives you healthy exposure to the housing market without over‑stretching.
- Leaves room for savings, investments, and lifestyle spending.
- Reduces financial stress and increases flexibility.