Clear sources. Clear calculations.

Income and budget before price

The main planner starts with each buyer’s annual income, monthly take-home pay (income after tax and other deductions), actual commitments, living costs, a chosen payment ceiling and available cash. It shows an initial budgeting check, not a lender affordability (whether the borrowing and ongoing costs fit your circumstances) assessment. Credit history, income type, dependants and retirement/change questions identify checks to make; they are not a proprietary credit or lender model.

Comparing particular homes

The home comparison reuses your current income-first budget, including fees, retained cash, loan assumptions and everyday spending. Entered property costs replace matching allowances. Blank amounts keep the labelled plan allowance. Annual Council Tax and property charges are divided by 12; they do not change payment schedules with the supplier. Home details and links are entered by you: nothing is imported or checked with a listing provider. Shared ownership (buying a share of a home and paying rent on the rest) and special purchases are excluded from the ordinary-home calculation.

How the starting price points are calculated

One borrowing input is your recent lender/broker figure, or a clearly labelled 4.5× gross-income illustration. The second is the loan repayable within the lower of your chosen monthly payment ceiling and take-home income minus the full entered monthly budget. We use the smaller loan figure. A second scenario repeats this at an interest rate two percentage points higher.

For each scenario, the calculator finds a price that fits current unrestricted cash, usable LISA (a savings or investment account with a government bonus and withdrawal conditions) money, purchase tax, buying costs and the retained reserve, assuming at least a 5% deposit. It rounds the result down to £1,000. Unknown tax prevents a complete price point. No mortgage (a loan secured on your home)-supported price is shown when the illustrated borrowing budget is zero. The model covers prices from £10,000 to £5m; product minimums and maximums are not assessed. These are scenario ceilings, not the lower and upper bounds of a lender offer.

When a scenario is selected, its income-and-budget borrowing cap remains in the saved plan and later comparisons. A higher-rate starting point retains that higher-rate cap. Extra saving does not raise the borrowing limit. A lender may accept different income, use different credit or household-cost assumptions, or decline the application.

Cash and borrowing

Required deposit is the larger of your selected percentage of the price and the difference between the price and the borrowing assumption. A checked borrowing figure replaces the 4.5× gross-income input. In the new main journey, borrowing is also limited by the completed monthly budget. Legacy saved scenarios are flagged for review and are not silently treated as having completed this check.

Two separate savings pots

Only eligible, confirmed LISA funds up to the deposit are applied to that deposit. The remaining deposit, buying tax, cash-paid costs and retained reserve must be covered by unrestricted cash. Unused or unconfirmed LISA balances are not treated as money for fees or a reserve. If you withdraw money under different permitted rules, enter only cash that is actually available in unrestricted savings.

Saving time

The remaining unrestricted cash gap is divided by sustainable monthly cash saving, rounded up to complete months. Prices, income and spending stay unchanged. Future LISA bonuses, savings interest, investments and purchase timescales are not projected. If tax is not established, no complete cash-target saving period is stated.

Monthly payments

Capital-and-interest repayment formula, monthly payments, constant entered interest rate over the whole term, no fees or overpayments. Total interest is total payments minus the loan. A rate two percentage points higher is a comparison, not a lender stress test or a forecast. The default 4.5% is an illustration, not a current product quote.

Tax scope

Only straightforward full residential purchases in England by individuals within the stated scope are modelled. Additional-property and non-resident cases, companies/trusts, mixed or linked transactions, shared-ownership tax and new-lease rent tax need separate checks. Unknown answers are not converted to a zero tax bill. Final SDLT (the property-purchase tax used in England) is rounded down to whole pounds.

Guided home bills and buying costs

The planner distinguishes published reference figures, editable example allowances and your own amounts. Unknown personal costs remain open. Local Council Tax references use MHCLG Table 9 for 2026–27. All area references include average parish or community charges and can differ from an address bill. A 25% discount is an explicit scenario, not an eligibility decision. Postcodes.io identifies the council area only.

Energy, water and home-insurance references are dated and linked in the planner. Broadband, repairs, charges, some fees and the £2,000 reserve are example assumptions, not verified personal costs. No savings timeline is calculated when monthly saving is unknown. Replace assumptions with property details and itemised quotes before relying on a budget.

Content and maintenance

Government, tax-authority and original lender sources support the rule explanations. MoneyHelper supports general preparation and cost guidance. These are selected examples, not a complete market search. No automatic updates are running; source dates are shown and rules can change.

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