Cash Isa battle sees Trading 212 push top rate to 5.01%, should you bag a best buy while you can?

Products featured in this article are independently selected by This is Money's specialist journalists. If you open an account using links which have an asterisk, This is Money will earn an affiliate commission. We do not allow this to affect our editorial independence.A week-long rates battle raging among easy-access cash Isa providers has culminated in Trading 212* pushing its interest rate to 5.01 per cent. The move came after Plum’s cash Isa* boosted its rate to 5 per cent, although it's only available until September 30.In good news for savers, this has pushed best buy easy access cash Isa rates above 5 per cent for the first time since early 2025.What savers need to be aware of is that providers have been constantly edging up rates in response to their competitors using bonuses.These are a fixed rate on top of the regular underlying variable rate that lasts for a limited time, in most cases 12 months.Tweaking this by small amounts allows providers to stay ahead of their rivals in the rates tables but you should also check what the underlying rate is.Meanwhile, these top bonus rates are usually only available to new customers, so those who have signed up before can't get them Trading 212: The investment platform also consistently offers a best buy cash IsaWhen rate tussles kick off, a tactic deployed by providers is to increase their cash Isa rate by a small amount – sometimes as little as 0.01 per cent – above whatever the market-leading rate is at the time.Trading 212 is often the platform that doesn’t back down, hiking its rate so that it stays at the top of the list of easy-access best buys. Its bonus is also considerably smaller than Plum's, which means Trading 212 customers get a stronger underlying rate of 3.6 per cent compared to its rivals 2.54 per cent.Here’s how the top accounts compare and our verdict on them overall.What should you look for when deciding on an easy-access cash Isa?Interest rates will probably play the biggest factor in your decision. Rates above 5 per cent currently beat inflation and forecasts for how high it will go over the next year, with a peak of about 4 per cent expected.Inflation rose by 3.1 per cent in August 2026, up from 2.9 per cent the previous month. This is measured by the Consumer Prices Index.By taking the top easy-access cash Isa rate of 5.01 per cent, this would theoretically give you a real return of 1.91 per cent when factoring in August’s inflation figure. However, inflation is a measure that looks backwards, while savings rates show what you should get in the future.Also keep in mind that easy-access cash Isa rates are variable, and the level of inflation month to month is difficult to predict.Here’s how the top four easy-access cash Isas by rate stack up: Easy-access cash Isas compared Trading 212* Plum* Hargreaves Lansdown* Chip Rate (variable) 5.01% 5% 4.52% 4.5% Underlying rate 3.6% (1.41% 12-month boost) 2.54% (2.46% 12-month boost) N/a - no boost 3.5% (1% 12-month boost Transfer rate 5.01% only on this year's contributions - 3.6% otherwise 3.75% 4.52% - must open with £1 and transfer to its stocks and shares Isa first 4.5% Minimum deposit £1 £1 £1 £1 Flexible Isa Yes Yes No Yes Withdrawal penalties No No No No Source: Information from the providers' websites Make sure you check the level of any 12-month boost. A higher underlying rate means that your rate won’t plummet by as much after the year, although it’s best to always check your options after that to see if you can switch to a better rate.Beyond this you should consider whether the account is truly easy-access – for example, whether it’s a flexible Isa. This type of account lets you withdraw money and replace it in the same tax year without reducing your Isa allowance.Look for any withdrawal penalties too. Some accounts penalise you by lowering your interest rate for making more than three withdrawals a year.And if you’re looking to transfer, it’s best to ignore the headline rates advertised by some providers – this is because they often apply a different one to existing funds.Boosted rates are only available to new customers of the provider.This is Money says... Trading 212’s easy-access cash Isa remains a top choice in terms of rate and flexibility. Find out more about Trading 212*.The underlying rate is the best out of the four accounts above. And if you transfer an Isa that includes contributions from this tax year, those will get the higher 5.01 per cent rate – but contributions from previous tax years get just 3.6 per cent.Trading 212 is primarily an investment platform, which offers fee-free trades and no account fees. Part of the business also offers high-risk investments in the form of CFD trading, which most retail investors lose money on, and should be avoided.For transfers, both investment platform Hargreaves Lansdown* and savings app Chip come out on top by rate. Savers wanting to transfer existing Isa pots should be aware there’s a quirk with Hargreaves Lansdown that means you must transfer to its stocks and shares Isa first. This is no good for those who have already used this year’s full £20,000 Isa allowance, because it requires you to open the cash Isa with £1 before transferring your money. This is only the case for transfers, if you just want to open a cash Isa this is done normally at HL. It’s also not a flexible Isa so replacing withdrawals hits your Isa allowance.SAVE MONEY, MAKE MONEYUp to £250 cashbackUp to £250 cashback2.5% cashback when investing at least £2005.01% cash Isa5.01% cash IsaTrading 212: 1.41% fixed 12-month bonus£3,000 cashback£3,000 cashback£100-£3,000 cashback when opening SippUp to £150 cashbackUp to £150 cashbackOpen a savings account with at least £5,000Welcome bonusWelcome bonusGet up to £200 when you invest £100Affiliate links: If you take out a product This is Money may earn a commission. These deals are chosen by our editorial team, as we think they are worth highlighting. This does not affect our editorial independence. Terms and conditions apply on all offers.