How to Lock In a Mortgage Rate Before It Rises
If you’re buying or remortgaging and worried about rates going up, you’re asking the right question at the right time. Mortgage rates can change quickly, and long purchase timelines mean delays can be costly.
The good news is that you can usually secure a mortgage rate in advance. The key is understanding how rate locks actually work, when they apply, and how to protect yourself without losing flexibility.
What “Locking In a Mortgage Rate” Really Means
In the UK, you don’t lock a rate with an Agreement in Principle (AIP). An AIP only confirms borrowing potential.
A rate is normally secured when:
You submit a full mortgage application
A specific product is selected
The lender issues a mortgage offer
From that point, the rate is protected for a set period, even if the lender later increases pricing.
How Long Can a Mortgage Rate Be Held?
Most lenders allow rates to be held for up to six months, depending on the product and whether it’s a purchase or remortgage.
This is particularly useful if:
You’re in a long property chain
You’re buying a new build
Your completion date is uncertain
Once locked, market movements don’t affect your rate during the offer period.
Why Timing Matters
Waiting too long can mean:
Products being withdrawn
Rates increasing before you apply
Fewer suitable options available
Applying too early without preparation can also cause problems if documents aren’t ready or circumstances change.
The aim is to apply as soon as you’re comfortable with the available rates, not when the media tells you to panic.
A Common Fear: “What If Rates Drop After I Lock In?”
This is one of the biggest concerns — and a valid one.
In many cases:
You can switch to a cheaper product with the same lender before completion
This does not usually require a full reapplication
It depends on lender policy and timing
This means locking early doesn’t always mean being stuck. You can protect against rises while still benefiting from future reductions, where allowed.
Common Mistakes to Avoid
Assuming an AIP protects you from rate rises
Waiting for “the perfect rate” before applying
Locking a rate without checking flexibility
Submitting an application without documents ready
These delays often cause people to miss opportunities rather than save money.
The Practical Step-by-Step Approach
A sensible process looks like this:
Review available products based on your situation
Decide when you’d be comfortable proceeding
Prepare documents in advance to avoid delays
Submit a full mortgage application to secure the rate
Monitor the market while the application progresses
Switch products before completion if a better option appears and rules allow
This approach balances protection with flexibility.
Who Should Consider Locking In Early?
Locking early is especially useful if:
You’re risk-averse and value certainty
Your purchase timeline is long
Rates are volatile
You’re close to affordability limits
If rates rise, you’re protected. If they fall, you may still have options.
How We Help
We explain available rates clearly before you commit
We submit the application to lock the rate on your behalf
We keep monitoring in case a cheaper option appears
There’s no obligation if you don’t like what you see
No pressure. No assumptions. Just clarity and control.
Key Takeaway
You don’t lock a mortgage rate by waiting — you lock it by applying.
In most cases, securing a rate early protects you from rises without removing all flexibility. The right timing, preparation, and ongoing monitoring matter far more than trying to predict the market.
If you’re worried about rates increasing, acting early — properly — is usually the safer move.
