Earlier finish
Time removed from your mortgage term.
Mortgage planning, made clearer
Make every pound
work harder.
See your payments, interest and overpayment options in one clear plan — without sharing your financial details.
Build your plan ↓Your numbers stay with you. This calculator runs entirely in your browser. Mortgage IQ does not collect or send your financial data. How this works
Your plan
Start with the facts.
Adjust the details below. Your forecast updates instantly.
Your forecast
A clearer way forward.
Your monthly payment——
Mortgage-free in—with your plan
Interest saved—vs no overpayments
Total interest—over your plan
Total paid—including upfront fees
Balance over time
With and without overpayments
The overpayment effect
Small habits.
Meaningful momentum.
On a repayment mortgage, overpayments reduce the balance on which interest is charged. Earlier overpayments generally have more time to make a difference.
Overpayments made
Extra capital paid under this plan.
Loan position
Add a property value to see your LTV.
Loan-to-value over time
Add a property value to see how your LTV falls.
Lenders price mortgages in LTV bands. The lower your LTV, the less risk they take, so the better (lower) the rates they usually offer. Common steps are 95%, 90%, 85%, 80%, 75% and 60%. Every time your balance falls below a band, cheaper deals may open up at your next remortgage. Assumes a constant property value.
Your mortgage journey
Know what comes next.
Set your deal end date for dated reminders, or use the current-rate period in your plan.
The detail
See the road ahead.
—
What if
Your custom forecast.
Balance with your lump sums
Compared with your current plan
Compare options
Is a new deal
worth it?
Test a prospective deal against your current plan. Fees and the initial rate are included to help you look beyond the headline rate.
Full comparison
Mortgage 1
vs Mortgage 2.
Mortgage 1 — from your planner
Configure your plan above to populate Mortgage 1.
Mortgage 2 — alternative
Turn on comparison to see results.
Scenario library
Keep your options in view.
Save useful what-if plans while you compare them. They are saved in this browser only, never sent anywhere.
Save the current plan
Capture your current inputs, forecast and overpayment approach as a named scenario.
No saved scenarios yet.Try a rate or overpayment change, then save it here to compare later.
Overpay vs save
Which works
harder for you?
Compare your overpayment strategy against putting the same amount in a savings account. General information only — not financial advice.
Tax band
Contributions are compounded monthly over your projected mortgage term. Savings rates are not guaranteed.
Add an overpayment in the planner to see the comparison.
UK mortgage habits
Plan with confidence.
General information, not personal financial advice.
Protect your buffer first
Consider keeping an emergency fund before committing spare cash. Overpayments are usually not easy to draw back out.
Check your deal rules
Many fixed deals limit penalty-free overpayments. Confirm your allowance and any ERC with your lender.
Review before your deal ends
Start reviewing options ahead of your fixed or tracker period ending. A product transfer or remortgage may be appropriate.
Compare the full cost
Look at fees, incentives, the rate and how long you expect to stay — not just the initial payment.