Lifetime ISA Bonus Calculator UK 2026/27

A Lifetime ISA can be attractive because the government adds a bonus to qualifying contributions, but the bonus is only one part of the decision. The account has an age-to-open rule, a £4,000 annual contribution limit, a first-home route with a £450,000 property limit and a 12-month waiting rule, plus a 25% charge for most other withdrawals.

Use the Lifetime ISA bonus calculator→ to model contributions, the government bonus, an illustrative balance to age 60 and first-home deposit scenarios. This is a calculator-workflow guide. The existing Lifetime ISA UK 2026/27 guide explains the account more broadly; this page focuses on how to enter assumptions and interpret the result without confusing a bonus with a guaranteed return.

Key takeaways

What the calculator is designed to show

The calculator has four useful jobs:

1. Estimate the government bonus generated by the contribution you enter.
2. Show how monthly or annual contributions could build an illustrative pot over time.
3. Test a first-home deposit scenario against an entered property price.
4. Compare the LISA assumptions with illustrative ISA and pension outcomes.

It is not an application form. It cannot confirm that you are a first-time buyer, that a property satisfies the legal definition of a qualifying home, that your provider will transfer the money in time, or that a projected investment return will occur. It also does not price provider charges, mortgage affordability or the full tax position of a pension withdrawal.

That distinction is important because a calculator can make a £1,000 annual bonus look certain while the real outcome depends on contribution timing and account eligibility. It can show a large balance at age 60 while ignoring inflation or a different retirement tax position. Use the results to compare assumptions, then verify the account and transaction rules with GOV.UK and the provider.

Step 1: check whether a LISA is available to you

GOV.UK says you must be 18 or over but under 40 to open a Lifetime ISA. You must also be UK resident, subject to the stated armed-forces and Crown-servant exceptions. The first payment must be made before age 40. You can keep paying into the account until age 50, but the government bonus stops after that point.

Enter your current age accurately. The age field is not only for a retirement projection: it affects whether opening and future contributions are possible. Someone who is 39 may have a very different contribution window from someone who is 25, even if both enter the same monthly amount. Someone who already has a LISA can continue to model contributions under the account rules, but a new account cannot be opened after the permitted opening age.

Do not treat the calculator’s ability to accept an age as confirmation that a provider must open the account. Provider onboarding, UK residence, identity checks and transfer rules still apply.

Step 2: enter contributions and cadence

The core formula is simple: a qualifying contribution receives a 25% government bonus, subject to the annual limit. A £1,000 contribution can generate a £250 bonus; a £4,000 contribution can generate a £1,000 bonus. Contributions above £4,000 do not generate more LISA bonus in that tax year, although the wider ISA rules and provider arrangements need separate consideration.

Monthly input should be converted carefully. A £333 monthly contribution equals £3,996 over twelve months, while £334 monthly equals £4,008 and exceeds the annual LISA contribution limit if paid for all twelve months. A calculator may round the display, so check the annualised contribution in the result rather than relying on the monthly label.

Annual contributions also have timing risk. Paying £4,000 in one transaction may produce a different investment path from paying monthly, particularly in a stocks and shares LISA. The same total contribution and bonus can still experience different market exposure, cash interest and provider charges. Run both a monthly and annual scenario if timing is part of the decision.

The LISA’s £4,000 contribution limit counts towards the overall ISA limit. GOV.UK states that the overall ISA limit is £20,000 for 2026/27. The calculator should therefore not be read as permission to contribute £4,000 to a LISA and another £20,000 to other ISAs without checking the total.

Step 3: choose cash or investments consciously

A LISA can hold cash or stocks and shares, or a combination of both. The calculator’s growth-rate field is an assumption, not a product recommendation. A cash LISA may use an interest rate that can change, while a stocks and shares LISA may fall as well as rise and will have charges, fund risk and a time horizon.

Use at least three growth scenarios, such as a low, central and high illustration. Do not present any of them as an expected or guaranteed return. Deduct or separately display provider charges where the tool allows it; a gross growth rate and a net-of-fee result are not the same.

For a first-home goal, the time until the money is needed matters. A contribution made today may be invested for less than 12 months, but the first-home withdrawal condition also depends on when the first payment into any LISA was made. A high-risk asset allocation close to exchange can create a mismatch between the calculator’s projected value and the amount available when the solicitor needs funds.

For a retirement goal, a longer horizon may support a different risk discussion, but the balance at age 60 is still nominal unless inflation is modelled. A £100,000 projection in future pounds does not have the same spending power as £100,000 today.

Step 4: model a first-home purchase

GOV.UK states that you can use LISA savings for a first home where all the relevant conditions are met. The property must cost £450,000 or less, the purchase must be at least 12 months after the first LISA payment, a conveyancer or solicitor must act and receive the funds directly from the provider, and the purchase must use a mortgage.

Enter the full property price, not only the deposit you hope to fund. The £450,000 test is a property-price condition. A £40,000 LISA balance does not make a £500,000 property eligible. The calculator should flag the property-price scenario but cannot assess every purchase structure or the first-time-buyer status.

The 12-month rule is another frequent mistake. It is measured from the first payment into the LISA, not from the date you first downloaded the app, opened an account application or began saving elsewhere. Keep evidence of the first payment and ask the provider how it records the date. If you expect to exchange before twelve months, model a delay or an alternative source of deposit rather than assuming a qualifying withdrawal.

If you buy with another person, GOV.UK says both people can use their LISA savings and bonus where both are first-time buyers and each meets the conditions. The calculator can model two balances as a planning exercise, but it should not turn one person’s eligibility into the other person’s eligibility.

Step 5: understand the withdrawal charge scenario

The permitted charge-free routes are important: first-home purchase under the conditions, age 60 or over, or terminal illness with less than 12 months to live. GOV.UK says a 25% withdrawal charge applies when money or assets are withdrawn for another reason.

The charge is not simply the bonus being removed. GOV.UK’s example shows that an initial £800 contribution receives a £200 bonus, creating a £1,000 pot before growth; a 25% charge on the whole pot leaves £750. If you need £120 in cash, you may need to withdraw more because the charge applies to the withdrawal amount.

Use the calculator’s early-withdrawal illustration to understand this arithmetic, not to optimise around a penalty. A market loss can also mean that the charge is applied to a smaller or larger balance than the original contributions. Transfer rules can have their own treatment, so check the provider and GOV.UK before moving money between account types.

Step 6: compare LISA with pension and ISA scenarios

The calculator may show a LISA versus pension or ISA comparison, but the accounts are not interchangeable.

LISA versus pension

A LISA gives a 25% bonus on qualifying contributions and charge-free access at 60, subject to the LISA rules. A pension can provide tax relief through the scheme and may receive employer contributions. GOV.UK explains that relief on private pension contributions can be automatic or claimed depending on the scheme, and that tax relief is generally available up to 100% of annual earnings, subject to the pension rules.

The pension comparison must therefore identify whether the contribution is salary sacrifice, net pay or relief at source, whether an employer contribution is available, and how retirement withdrawals will be taxed. A LISA may be useful for someone who values a first-home route or tax-free access at 60; a pension may be stronger where employer matching or higher-rate relief is available. The calculator cannot value a defined-benefit promise or decide the best retirement vehicle.

LISA versus ISA

An ordinary ISA can be more flexible for non-qualifying access because it does not use the LISA’s 25% withdrawal charge in the same way. A LISA, however, adds a government bonus to eligible contributions and can be used for a qualifying first home. The comparison should show the value of flexibility rather than only the ending balance.

The annual allowance also matters. GOV.UK states that the overall ISA limit is £20,000 for 2026/27 and that the LISA’s £4,000 limit counts within it. A scenario that contributes to a LISA and a stocks and shares ISA should show the total ISA funding, not assume two separate £20,000 allowances.

Step 7: run decision-relevant scenarios

Useful scenarios include:

Common input mistakes

Confusing the bonus with a return

The bonus is a rule-based addition to eligible contributions. Investment growth, cash interest, fund charges and inflation are separate. A £1,000 bonus does not mean the account earned £1,000 from investment performance.

Ignoring the first payment date

The first-home route requires the purchase to be at least 12 months after the first payment. Record the date and keep a buffer if the transaction timetable is uncertain.

Using the LISA for an ineligible property

The £450,000 condition is not a suggested target price. If the home is above the limit, model the deposit using an ISA, cash or another permitted source and check the transaction with the provider.

Treating the 25% charge as a small fee

It can recover more than the government bonus because it applies to the amount withdrawn, including the bonus and potentially growth. Run the full-pot example before committing money needed for an emergency.

Comparing products with unequal assumptions

A pension scenario with employer matching should not be compared with a LISA scenario that excludes the employer contribution. An ISA scenario with no charge may be more flexible but may not receive a government bonus. Label each assumption.

Record the result and verify the provider terms

The calculator result should be saved with the date, tax year, contribution cadence, property price, growth assumption, current balance, account goal and withdrawal setting. Provider charges, fund availability, transfer timing and interest rates can change independently of the statutory LISA rules.

For a first-home purchase, ask the provider and conveyancer how the withdrawal is requested, how the funds are paid to the conveyancer, what evidence is required and how the 12-month condition is checked. For retirement saving, check whether the account is cash or investment-based, the charges, access process and beneficiary arrangements. A general guide cannot replace those account-specific terms.

Frequently asked questions

Official sources and next steps

The rules and figures in this guide are based on the following official sources. Check them again before opening or withdrawing because provider procedures and tax-year guidance can change:

• GOV.UK — Lifetime ISA overview
• GOV.UK — Who can open a Lifetime ISA
• GOV.UK — Withdrawing money from a Lifetime ISA
• GOV.UK — Individual Savings Accounts
• GOV.UK — Pension tax relief
• GOV.UK — Workplace pension contributions

Start with the Lifetime ISA bonus calculator→, then read Lifetime ISA UK 2026/27, Pension versus ISA and ISA growth planning for broader comparisons.

Official sources

• GOV.UK: Lifetime ISA overview
• GOV.UK: Who can open a Lifetime ISA
• GOV.UK: Withdrawing money from a Lifetime ISA
• GOV.UK: Individual Savings Accounts
• GOV.UK: Pension tax relief
• GOV.UK: Workplace pension contributions

These GOV.UK pages are the official references for Lifetime ISA eligibility, the government bonus, withdrawals, ISA rules and pension comparisons. Check the current age, purpose and withdrawal conditions before contributing.