Useful next calculations
When to use this calculator
- Before comparing mortgage products, brokers or repayment types.
- When you want to test how a different deposit, rate or term changes the payment.
- When you need a quick estimate before using a formal illustration or agreement in principle.
- When you are stress-testing your budget against a higher rate.
A worked example
These are the example figures the calculator opens with.
| Input | Value |
|---|---|
| Target property price (£) | £300,000 |
| Deposit already saved (£) | £18,000 |
| Selected LTV milestone (%) | 90% |
For those figures the calculator returns:
- Target deposit: £30,000.00
- Remaining to save: £12,000.00
Method & assumptions
This deposit planner converts a target property price and chosen LTV milestone into a cash-deposit target. It compares that amount with savings already set aside and projects an optional monthly saving plan using an entered net savings rate.
It deliberately keeps transaction costs outside the deposit target; first-time buyers should calculate the full cash-to-complete figure before treating the target as funded.
LTV bands are planning milestones, not lender offers. Property value, affordability, product availability and underwriting can all affect the final mortgage terms.
Common mistakes
- Mixing up loan amount and property value, which can distort affordability and LTV.
- Using a headline rate but forgetting fees, insurance, taxes or repayment type.
- Testing only one term length instead of comparing the payment and total cost together.
- Forgetting that a repayment mortgage and an interest-only mortgage produce very different monthly figures.
What to do next
- Run a second scenario with a higher rate or shorter term so you can see the downside clearly.
- Compare the result with an affordability or overpayment calculator before applying.
- Note the monthly payment and total interest for your strongest scenarios before you speak to a broker.
- Check whether a modest overpayment would reduce total interest — use the overpayment calculator next.
Questions people ask
Loan-to-value is the mortgage amount as a percentage of the property value. A lower LTV means a larger deposit or more equity.