Cash ISA vs Stocks & Shares ISA vs LISA
There are three main types of ISA and they do very different things. Here's what each one is for, who it tends to suit, and how to work out which fits what you're saving for.
An ISA is an Individual Savings Account. Think of it like a protective box you put your money in — anything inside it grows tax-free. Interest, investment gains, dividends — none of it gets taxed. The money inside can be cash, investments, or both. The ISA itself isn't the investment — it's the shield around it.
Every tax year (April to April), you can put up to £20,000 into ISAs. If you don't use that allowance, it's gone — it doesn't carry over. And it's shared across all ISA types, so you can split it however you like: £10k in a Cash ISA and £10k in a Stocks & Shares ISA, or chuck the whole £20k into one. Your call.
The three ISAs, compared
Example context
Based on Sam, 28, earning £38,000/year, saving for a house deposit in 3-5 years. No existing ISA.
Capital at risk. Stocks & Shares ISAs and Stocks & Shares LISAs are investments. The value of your investment can fall as well as rise, and you may get back less than you invest. Past performance is not a reliable indicator of future results. This guide is general information — it is not a personal recommendation to buy any investment product.
Cash ISA
Savings account where interest is tax-free.
Best for
Short-term savings (1-3 years). Topping up your emergency fund. Money you absolutely cannot afford to lose.
Typical return
4-5% interest (changes with the market, depends on provider)
Risk
Basically zero — your money is protected up to £85k by the government's savings safety net.
Annual limit
£20,000/year (shared across all ISAs)
Access
Usually instant. Some fixed-rate accounts lock your money for a set period.
Watch out
The interest often doesn't keep up with rising prices long-term. Your balance goes up, but what it can buy might not.
Stocks & Shares ISA
Investment account where growth and dividends are tax-free.
Best for
Growing your money over the long run (5+ years). A good partner to your pension. Where your money actually works for you.
Typical return
5-8% average historically (not guaranteed — some years more, some years less)
Risk
Your capital is at risk. The value of investments can fall as well as rise, and you may get back less than you put in. Past performance is not a reliable indicator of future results.
Annual limit
£20,000/year (shared across all ISAs)
Access
You can sell and withdraw anytime, but if markets are down when you sell, you lock in that loss.
Watch out
You need to actually invest the money once it's in there — just opening the account and leaving cash sitting in it earns you nothing.
Lifetime ISA (LISA)
Savings/investment ISA with a 25% government bonus, for house deposits or retirement.
Best for
First-time buyers under 40 saving for a home (property must be £450k or under). Also works as extra retirement savings on top of a pension.
Typical return
25% bonus from the government, instantly — plus any interest or growth on top
Risk
Cash LISA: zero risk to your capital. Stocks & Shares LISA: your capital is at risk — the value can fall as well as rise, and you may get back less than you put in.
Annual limit
£4,000/year (this counts towards your £20k total ISA allowance, not on top of it)
Access
You can only take it out penalty-free for your first home or after you turn 60. Take it out for anything else and you lose 25% — you actually get back less than you put in.
Watch out
The £450k property price cap rules out most of London and some other cities. And that 25% penalty is brutal if your plans change.
So which one should you use?
Honestly, it depends on what you're saving for and when you need the money. Here's the quick way to think about it:
Need the money in under 3 years? Cash ISA. You can't afford to ride out a market dip if you need the money for a deposit next year.
First-time buyer, property under £450k? LISA for the 25% government top-up — about as close to free money as the system gives you. But keep it in a Cash LISA if your timeline is under 5 years. S&S LISA only if you're buying 5+ years from now.
Won't need it for 5+ years? Stocks & Shares ISA. Over longer stretches, investments have historically grown much faster than cash savings. The bumps along the way smooth out when you zoom out.
You can combine them. A common approach for someone like Sam: £4,000/year into a LISA (£1,000 bonus), the rest into a S&S ISA for long-term growth. Emergency fund stays in a separate easy-access savings account.
Sam's example
Sam wants to buy in 3-5 years. With £200/month to save, a LISA makes sense for the bonus — that's £2,400/year, with a £600 government bonus on top. For anything beyond the £4,000 LISA limit, a Cash ISA keeps the rest tax-free and accessible.
The real cost of not using your ISA allowance
Roughly 60% of UK adults don't have an ISA. That means they're either earning interest in a normal savings account (where the taxman takes a cut once you earn over a certain amount) or not saving at all.
Right now, if you're a basic-rate taxpayer, the first £1,000 of interest you earn is tax-free (it's called the Personal Savings Allowance). But with savings rates at 4-5%, you hit that limit with just £20,000-£25,000 saved. After that, every pound of interest gets taxed at your normal tax rate.
An ISA removes that problem entirely. Everything inside it grows tax-free — no limit. And while you can only put in £20k per year, there's no cap on your total ISA balance. It can grow as big as it likes.
Illustrative projection only. Uses a 5% average annual return after fees, which is not guaranteed. Your actual returns may be higher or lower. The value of investments can go down as well as up.
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