The calculator uses the deposit target you set
That keeps the plan anchored to a real property budget instead of a generic nationwide average or an arbitrary "ideal deposit" number.
Deposit Calculator
Deposit calculator for savings plans, gifts and Lifetime ISA top-ups
Build a deposit target, compare regular savings with a gift or Lifetime ISA top-up, and keep the wider buying budget separate from the deposit pot itself.
Deposit-only planningLISA timing and property-cap checksGift and savings route comparison
Starting Point
Many buyers plan around a 5% to 10% deposit
Pricing Context
Larger deposits usually improve pricing, with around 40% often strongest
LISA Rule
First-home use still needs a 12-month holding period and a property price of £450,000 or less
Planner
Build the deposit pot first, then test how you want to fund it
Use the planner below when the goal is to understand the deposit target and the saving path to get there. It models three realistic funding routes: regular savings, a cash gift and a Lifetime ISA top-up.
Deposit Target
£
%
Target deposit: £30,000
£
£
%
Use your own realistic savings rate rather than a guessed market default.
Savings Timeline
Target Deposit
£30,000Still To Build
£25,000Time To Target
3 years 9 monthsFuture Contributions
£22,500Interest Earned
£2,539Projected Deposit Pot
£30,039Deposit checkpoints worth checking first
5% to 10%: Many buyers start by testing a deposit in this range against the property budget they want.
40%: Larger deposits usually open up stronger pricing, with around this level often sitting in the most competitive part of the market.
This planner shows the funding timeline rather than promising a mortgage rate at each milestone.
Method
How this planner handles deposit routes
Deposit planning gets distorted when pages treat every loan-to-value band like a fixed mortgage-rate step. This planner keeps the focus on the cash target and the route to reach it.
Gift and LISA routes are treated as funding routes, not lender approvals
The calculator shows what happens to the cash timeline, while leaving lender acceptance, evidence and paperwork to the next stage where those questions actually belong.
Lifetime ISA support is checked against the current home-buying rules
The planner now warns on the 12-month holding period and the current £450,000 property cap, so it does not overstate how quickly the money can be used.
Buying costs sit outside the deposit plan
This keeps the deposit separate from the full cash needed to buy, which still includes legal fees, surveys, removals and tax where relevant.
Funding Routes
The three deposit routes that materially change the plan
The real value here is seeing what each funding route changes, how much time it saves and which questions still need to be handled separately.
Regular savings
Use this route to test whether the deposit goal still works without outside help. It is the cleanest benchmark because every other route should beat this one for a specific reason, not because it sounds better on paper.
Gift top-up
A gift can move the target date dramatically, but the calculator now treats it as cash only. It no longer makes up universal rules about which donors all lenders will or will not accept.
Lifetime ISA top-up
The Lifetime ISA route can be powerful because of the 25% bonus, but the planner shows the current allowance cap and the 12-month and property-cap rules so the route does not get overstated.
Other Cash To Plan
The parts of the purchase budget that still sit outside the deposit
A deposit plan only becomes useful when it stays in its lane. These are the items to budget separately once the deposit route is clear.
Mortgage pricing still changes by lender and product
The calculator does not promise a fixed rate improvement at every deposit milestone. Those gaps move too often, and they do not behave the same way across the market.
Gift acceptance still needs lender paperwork
Whether a gift is acceptable and what proof is needed are still lender and case specific. The calculator only shows what the gift changes in cash terms.
Buying costs still need their own budget
Legal fees, surveys, removals and stamp duty can all change the cash you need on top of the deposit, so they should be planned separately.
Next Tools
Use the follow-on tools once the deposit plan is credible
The best next step depends on what is still missing after the deposit route is clear.
Lifetime ISA Calculator
Move here if the real question is whether a LISA timeline still works under the current rules.
Fees and Costs Calculator
Add legal fees, surveys and moving costs so the deposit is not treated as the full cash requirement.
Stamp Duty Calculator
Bring current SDLT into the purchase budget before making an offer or comparing areas.
Affordability Calculator
Check whether the property budget still works once the deposit route is in place.
Frequently Asked Questions
How much deposit do buyers usually need?
Many buyers start with a deposit of around 5% to 10% of the property price. Larger deposits usually open up stronger pricing, with around 40% often sitting in the most competitive part of the market. This planner lets you test your own target instead of relying on a fixed rate table.
Does this planner tell me which deposit size gets the best mortgage rate?
No. It is a funding planner, not a live-rate engine. Mortgage pricing changes by lender, product and timing, so the focus stays on the cash target and how long it takes to build it.
Are legal fees, surveys and stamp duty included in the deposit target?
No. The deposit is only one part of the purchase budget. You still need a separate cash plan for legal fees, surveys, removals, stamp duty and other buying costs.
How can a Lifetime ISA change the deposit plan?
A Lifetime ISA can add a 25% government bonus on up to £4,000 of contributions each tax year, but the first-home route still needs the account to have been open for at least 12 months and the property price to be £450,000 or less.
Does the gift tab tell me whether a lender will accept a gifted deposit?
No. The gift tab only shows how a cash top-up changes the saving timeline. Lender acceptance, source-of-funds evidence and gift paperwork still need to be checked with the lender or adviser.