How the calculator works
The maths is deliberately simple, because the point is a date you can actually plan around — not a spreadsheet you argue with.
First it works out your target pot: the deposit you're aiming for (5%, 10% or 15% of your target property price) plus a buffer of around £3,000 for the buying costs that sit on top of every deposit — legal fees, searches, a survey, moving. Most first-time buyers only discover that pile after they've offered; we include it by default so your date is honest. (You can untick it on your result if you'd rather see the deposit-only date — it updates live.)
Then it takes what you've already saved, subtracts it from the target, and divides what's left by your monthly saving. The answer is a number of months, which becomes your month and year: your keys date. If you're saving in a Lifetime ISA, work out the bonus you expect under the current gov.uk rules and include it in your monthly figure — that way the date reflects your actual entitlement, not a one-size-fits-all assumption.
Everything runs in your browser. No email, no signup, nothing stored.
A worked example
Say you're aiming at a £250,000 home with a 10% deposit, you've saved £10,000, and you can put away £500 a month.
- Deposit target: £25,000. Plus the £3,000 costs buffer → £28,000 total pot.
- You're £18,000 short. At £500 a month, that's 36 months — three years.
- Find an extra £85 a month — a Lifetime ISA bonus you've checked you qualify for, a trimmed subscription stack, a windfall pre-assigned — and the date pulls forward to 31 months. Small monthly changes move the date more than people expect.
That's the whole point of knowing your date: once it's a real number, you can see exactly which levers move it.
What it deliberately leaves out
An honest calculator tells you what it doesn't know. This one assumes your monthly saving stays flat — no pay rises, no windfalls — and it doesn't model savings interest, house-price changes, or mortgage rates. Prices in your area may drift up while you save; your saving power will probably grow too. Those pushes roughly trade off, but nobody can promise how they'll net out, so we don't pretend to.
It also isn't an affordability check. What a lender would actually offer you depends on your income, credit file and circumstances — that's a conversation for a qualified, regulated adviser when you're ready, and we're not that. General education only.
Five ways people pull their keys date forward
- Look into the Lifetime ISA early. If you qualify, the government adds a bonus to what you save — but the rules (age limits, property price cap, minimum account age, contribution limits, withdrawal penalties) are real, so read them on gov.uk first. If it fits your plans, the sooner it's open the better; work out what it's worth to you and add it to your monthly figure above.
- Automate the saving. A standing order on payday beats willpower every month. People who automate rarely miss the money; people who "save what's left" rarely have any.
- Attack the big three costs. Rent, transport and subscriptions move your monthly number far more than skipped coffees ever will. One flat-share year can shave months off the date.
- Pre-assign windfalls. Tax rebates, bonuses, birthday money — decide now that they're deposit money, before they arrive with other plans.
- Rethink the deposit percentage. A 5% deposit gets you in sooner; a bigger one usually means better rates and lower monthly payments. There's no universally right answer — but flick between the options above and watch how your date moves. Choosing deliberately beats drifting.
Questions people ask
It's an honest illustration, not a promise. The calculator uses your real numbers plus simple, published assumptions — a buying-costs buffer and, if you tick it, the Lifetime ISA bonus. It deliberately doesn't guess at house-price changes, savings interest or your future pay rises. Treat the date as a realistic baseline you can beat.
By default, a buffer of around £3,000 for the costs that surprise most first-time buyers — legal fees, searches, a survey and moving costs. The exact amount varies by price and region, so treat it as a sensible cushion rather than a quote. You can untick it on your result to see the date for your deposit alone, and the "What's this?" link breaks down what it typically covers.
Not automatically — on purpose. The LISA bonus depends on rules that are yours to check: age limits, a property price cap, a minimum time the account must be open, annual contribution limits and withdrawal penalties. Work out the bonus you expect under the current rules on gov.uk and include it in your monthly saving amount — then your keys date reflects your real situation, not a generic assumption.
No. The calculator is free, instant and runs entirely in your browser — nothing you type here is sent to us or stored anywhere.
Then today's job isn't the date — it's the setup. Getting your credit file tidy, your spending mapped and your first standing order in place (even a small one) is how every deposit starts. That groundwork is exactly what the getting-ready step of Your Property Mate covers.
Your date is the start, not the finish
Knowing when you could buy is step one. The expensive part of buying a first home is everything after the deposit — the mortgage setup, the viewings, the offer, the legal maze. Members typically pull their keys date forward and walk in knowing which levers to pull first. That's what Your Property Mate is for.
See if you qualify →Your Property Mate provides general educational information about the home-buying process only. It is not regulated financial, mortgage, legal or tax advice — figures shown are illustrative. Always seek advice from an appropriately qualified and regulated professional before making financial decisions.