Lightyear Cash ISA vs Trading 212 Cash ISA (2026): Which Actually Pays More?

Short answer: it depends whether you're chasing a bonus. Lightyear's Cash ISA pays a flat 3.75% AER that simply tracks the Bank of England base rate — no bonus, no catch. Trading 212's standard rate is lower, at 3.60% AER, but a genuinely new customer opening an account through a promotional link can currently get a combined rate of around 4.61% AER for 12 months (MoneySavingExpert, 28 August 2026). After that year — or on any older money you transfer in — Trading 212 drops back to 3.60%, which is less than Lightyear pays.

We compared both providers' own pricing and help-centre pages, plus independent UK comparison sites, all checked on 28 August 2026. We haven't personally opened either account for this piece — everything below comes from documented terms.

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The quick answer

• No bonus, ongoing rate: Lightyear wins. Its Cash ISA pays 3.75% AER, tracking the Bank of England base rate exactly, with no expiring bonus.
• New customer, first 12 months: Trading 212 wins. Its promotional links currently combine to around 4.61% AER (3.60% standard rate plus a 1.01-point bonus, via MoneySavingExpert's own promo code, checked 28 August 2026) — though other partner links have shown slightly lower combined rates, so the exact figure depends which one you use.
• Transferring an old ISA balance: Lightyear usually wins, because Trading 212's bonus doesn't apply to money from previous tax years.
• After the bonus ends: Lightyear wins again — Trading 212 reverts to 3.60%, a full 0.15 percentage points below Lightyear's rate.
• Bank Rate is 3.75%, held for the fifth time on 30 July 2026, with the next decision due 17 September 2026 (MoneySavingExpert).

How each rate is actually built

An ISA (individual savings account) shelters savings interest from UK tax, up to your annual allowance. AER — Annual Equivalent Rate — is the standard way to compare what you'd earn over a year if the rate and balance stayed the same, so it's the number to look at across providers.

Lightyear's Cash ISA is deliberately simple. It's built to track the Bank of England base rate directly, with — in Lightyear's own words — no asterisks. As of 28 August 2026 it pays 3.75% AER, matching a base rate that's also 3.75%. There's no bonus period, no minimum deposit, and it's a flexible ISA, meaning you can withdraw money and pay it back in during the same tax year without losing that part of your £20,000 allowance.

Trading 212's Cash ISA has two layers. The standard rate tracks the same base rate, but 0.15 percentage points below it — what Trading 212 calls its "tracking rate" — giving 3.60% AER today. On top of that, eligible new customers can earn a fixed bonus for a set period, usually 12 months, if they open the account through a qualifying promotional link or code, are UK residents with no existing or previous Trading 212 account, and make a first deposit within 10 days during the current tax year. As of 28 August 2026, MoneySavingExpert's own promotional code gives a 1.01-point bonus, for a combined 4.61% AER — though other independently reported links have shown bonuses closer to 0.9 points, so the exact combined figure is link-specific and changes over time.

The honest catch with Trading 212's number: it's genuinely a temporary, campaign-specific rate, not a fixed feature of the account. Lightyear's 3.75% is the account's actual, ongoing rate.

Side-by-side comparison (28 August 2026)

Rates checked against each provider's own pricing pages and MoneySavingExpert on 28 August 2026. Both rates are variable and can change with little notice — confirm the live figure before applying.

The bonus trap, explained honestly

This is the single thing to understand before picking a side: Trading 212's headline number is mostly a temporary bonus, not a permanent feature.

Strip the bonus away and Trading 212 pays 3.60% AER — 0.15 percentage points less than Lightyear's plain 3.75%. The only way Trading 212 comes out ahead is during a 12-month introductory window, and only if you qualify as a genuinely new customer depositing current-tax-year money.

That's not a reason to dismiss Trading 212. A year at 4.61% on, say, £10,000 works out to roughly £461 in interest, versus about £375 at Lightyear's 3.75% — a difference of around £86 for that first year. But you have to actually manage it: diarise the date the bonus ends, and be ready to compare rates again and potentially move your money, because Trading 212 won't automatically keep you on a competitive rate afterwards.

If you'd rather not play that game at all, Lightyear's flat 3.75% is the calmer option — you get a rate close to the top of the ongoing (non-bonus) market without anything to remember or diarise.

Is your money safe with either one?

Yes, to the same standard. Neither Lightyear nor Trading 212 is a bank itself — both hold your Cash ISA money with partner banks under UK client-money rules, and both are FCA-authorised.

• Trading 212 places cash with partner banks including Barclays, NatWest and JPMorgan.
• Lightyear places cash with partner banks including Citibank and NatWest.

Each of these partner banks is covered by the Financial Services Compensation Scheme (FSCS), the UK's deposit protection scheme, up to £120,000 per eligible person, per banking group — the higher limit that took effect on 1 December 2025 (up from £85,000). That £120,000 is shared across everything you hold at the same banking group, so if you already bank directly with, say, NatWest, it counts toward the same cap as any Cash ISA cash held there through either app.

Neither app offers phone support — Trading 212 gives you in-app live chat or a help-centre ticket, and Lightyear works the same way through its app and help centre.

Who should pick what

• You want a rate you can trust without watching the calendar: Lightyear. 3.75% AER, no bonus to track, no cliff-edge.
• You're a genuinely new customer to Trading 212, opening with new money this tax year, and you're organised: Trading 212's promotional rate is worth taking for the 12-month window — just set a reminder for when it ends.
• You're transferring an old Cash ISA balance: Lightyear, in most cases, since Trading 212's bonus typically excludes previous-tax-year money and you'd likely be left on its lower 3.60% standard rate.
• You already have cash sitting in a Trading 212 Cash ISA from a bonus that's ended: compare it against Lightyear's 3.75% — moving could be worth the hassle. Our wider best Cash ISA rates roundup tracks other options too.
• You're deciding between locking a rate in and staying flexible at all, rather than just picking a provider: see our fixed vs easy-access Cash ISA guide for that broader decision.
• You also want to compare these two as full investing apps, not just their Cash ISAs: our Trading 212 vs Lightyear comparison covers fees, ISAs and pensions side by side.

What the April 2027 ISA changes mean here

Neither of these Cash ISA decisions escapes the wider change coming to cash ISAs. From 6 April 2027, the cash ISA subscription limit for under-65s is due to fall from £20,000 to £12,000 a year, though the overall £20,000 ISA allowance stays the same. That doesn't affect a balance you already hold in either Lightyear or Trading 212's Cash ISA — it only affects new contributions from that date. We've covered the detail, including what to do before the change, in our guide to the 2027 cash ISA allowance cut.

How to open a Cash ISA with either provider

1. Decide what matters more to you: the highest possible short-term rate (Trading 212's bonus) or a simple, ongoing rate you don't have to manage (Lightyear).
2. For Trading 212, check you qualify as a new customer — UK resident, no existing or previous account — and open via a current promotional link or code so the bonus applies from day one.
3. For Lightyear, just download the app and open the Cash ISA — there's no promotional code to chase, since the rate is the same for everyone.
4. Deposit within 10 days if you're claiming a Trading 212 bonus, since that's a condition of the promotion; Lightyear has no such deadline.
5. If you're transferring an existing ISA, use the provider's official transfer process, never a withdrawal, so the money keeps its tax-free status. Ask your old provider to report which portion is a current tax-year contribution if you're hoping it'll qualify for a Trading 212 bonus.
6. Set a reminder for 12 months' time if you go with Trading 212's bonus rate, so you can compare again before it reverts to 3.60%.

This is general information, not financial advice. Rates are as reported on 28 August 2026 and are variable — always check the live rate and terms on the provider's own site before applying. FSCS protection depends on the authorised firm and banking group holding your deposit. Do your own research and consider speaking to a qualified adviser about your situation.

Last updated: 28 August 2026.