Which AI tool is best for ISA advice?

I agree that cash, or near cash, is a sensible approach for money that’s needed in two years. We wouldn't usually recommend investing money you'll need within five years, as there may not be enough time to ride out the ups and downs of the market.

A fixed rate savings bond could also work well, but you’d need to consider your wider tax position. A Cash ISA could be the right call, and it’s good that Claude points out that the interest earned on the £40k could exceed the personal savings allowance.

Money market funds are a reasonable suggestion if that £40k is already held within a Stocks & Shares ISA. In that case, they offer a simple way to earn a competitive rate without leaving the wrapper. But it’s a shame Claude doesn’t ask where the cash is currently held, as that would have improved its response.

Short-dated gilts are certainly an option, and I’m glad that Claude mentions holding them to redemption, although there’s quite a lot of jargon here. The FSCS point is sensible and they’ve kept that short and sweet.

It’s also good that it picked up on the user’s nervousness and gave a common-sense nudge on separating short term cash from long term investments. Overall, this is a good answer with lots of useful information.

Richard Caldicott

Grade: B

Artificial intelligence is a really powerful technology if used well. Large language models are trained on huge amounts of text but outputs vary hugely. Responses are rarely 100% right nor are they 100% wrong. So, the user has to decipher and interrogate the responses they receive while keeping an eye out for the information not included.

With the individual’s two-year time horizon, holding funds in cash is appropriate as Claude suggests. However, while fixed-term savings accounts give certainty around the interest rate over the term, the individual might benefit from the flexibility of holding some money in an easy access account especially if they can get a decent savings rate that is similar to the fixed rate.

LLMs like to tell us we are right, playing into our existing views with empathy. Claude noted that equities can ‘easily’ fall 20%. While it is true that markets can fall by this amount, it isn’t the norm. As a result, the LLM might be feeding into the individual’s anxiety about investing risk. I would have spoken to the individual more about the money and existing investments while trying to understand what the purpose of the £40,000 was in two years’ time. This would help shape the recommendation and response I gave them.

Charlotte Wheeler

Grade: B

This is a great start. It’s right to point out that cash is a sensible option and I like that it explains why. Suggesting a fixed-rate savings account is also reasonable, with useful warnings around early access and checking the maturity date fits your plans. I like that it then builds on this by suggesting some is kept more accessible, which is a nice practical touch.

It’s good to suggest a Cash ISA and explain why, but it misses that only £20,000 can be paid into ISAs this tax year. With £40,000, you’d therefore need to split the money.

Mentioning FSCS protection is also sensible, but the response could be more personalised by explaining that £40,000 held with one provider would be covered. Like Claude, it also doesn’t ask where the cash is held. If it's sitting in a stocks and shares ISA, a money market fund could keep it earning a competitive rate without leaving the wrapper.

It’s picked up on the move out of investments and rightly flags the risk of inflation, which is good to see.

Overall, this is a solid and measured response that doesn’t stray into the territory of recommendations.

Richard Caldicott

Grade: B

ChatGPT has gone down a different route to the other LLMs and tried to share a useful checklist with the individual. This is easier to digest and actionable for the reader. It has also reflected on the existing investments and provided some considerations, which is helpful. That said, the advice isn’t particularly in-depth and doesn’t soothe the individual’s concerns about investment risk. As a result, the individual might benefit from expert support on their existing investments as they could consider winding down the portfolio in stages to navigate market volatility. If I was responding to this individual, I would have created a plan for unwinding the investment portfolio if that is their wish and then provided some suggestions on how they could manage the cash savings both in year 1 and 2 as their ISA allowances refresh.

I was most intrigued to see how the LLMs played back risk to the individual. Out of the three LLMs, only ChatGPT mentioned the risk of inflation eroding the purchasing power of the individual if they moved their investments into cash savings. This is a large oversight when considering the purchasing power of the savings when UK inflation is tracking at 3.5% and has risen significantly in recent months. It’s important for the individual to understand inflation risk so they have the full facts before making a decision about their investments and savings.

The response doesn’t signpost individuals to other sources of information which would be handy if they wanted to find further details or fact check information. For example, if individuals are worried about their savings being protected, they could consult the FCA Firm Checker tool. If the existing investments are in a Stocks & Shares ISA, they might want to consider a transfer into a Cash ISA too. They could also shop around for the best platform or account, so they get the best deal if they are looking at Gilts, money market funds or savings accounts.

Charlotte Wheeler

Grade: B

This is a much more direct response that goes as far as making recommendations. Given the relatively clear brief, you could argue this response is the most useful. It’s good that it acknowledges the nervousness, and that the £20,000 ISA allowance may require you to split the funds into different pots.

There are some issues though. The FSCS limit is wrong. It’s £120,000, not £85,000, since the limit went up in December 2025. While this doesn’t impact the user in this case, it highlights the risk of AI pulling from out of date information. Quoting rates and naming providers could also be risky, as rates move quickly and the information would soon become outdated.

The response also doesn't ask where the cash is currently held and, unlike the other answers, it doesn't question the decision to move long-term investments into cash because of nerves.

Without probing further into the readers objectives and circumstances, these recommendations are perhaps premature and could lead to a poor outcome. That said, the answer hits all the main points based on the brief provided and its punchy style does make it more engaging.

Richard Caldicott

Grade: C

One of the biggest risks of using an LLM for financial decisions is acting on information which is misleading, incorrect or not shared. As we see here, the Gemini response provides outdated information. Gemini said that savings deposits were protected up to £85,000 per person, per banking institution when this figure increased to £120,000 in December 2025. It further doesn’t reflect on the upcoming Cash ISA rule changes which could impact the individual during their saving period.

Furthermore, it is concerning that the tool says their suggestions come with ‘zero risk’ when holding money in cash does come with risk, in particular, inflation risk. Very few financial decisions come with ‘zero risk’ so this catch all phrase is misleading and should be a red flag to the reader. One area the LLM did get correct is that OakNorth Bank and DF Capital are currently offering a two-year fix for 5.2% at the time of writing (21st October 2026). The individual may want to check whether these are the best deals on the market with online comparison websites.

It was positive to see the LLM asking the individual a question back about tax implications and trying to give them extra support. These added details, if provided, could help the individual uncover further information before they take a decision. Similar to Gemini, I’d have tried to find out more about the individual’s situation to build up a full picture of what they are trying to achieve with this money i.e. are they trying to get the best saving rate, reduce investment risk, or manage their potential tax liabilities?

Charlotte Wheeler

Grade: D

This is a good example of the importance of human judgement. AI can be a really useful starting point for understanding your options, but it won’t always pick up on the nuances of your situation. An answer can sound confident and engaging and still be wrong. So, it’s important to check anything significant with a trusted, regulated source if you can. There’s also the emotional support an adviser can give you which a bot can’t – if you’re about to make one of the biggest financial decisions of your life, it’s understandable to want a real person to talk you through it.

Richard Caldicott

Charlotte felt the bots tend to tell us what we want to hear, which risks feeding the reader’s anxiety rather than helping them think it through. Claude’s line that markets can “easily” fall 20%, for example, is true but isn’t the norm. For her, the power of a good adviser is in the asking of pertinent, relevant questions that would help shape the best plan for the reader's money.

Charlotte Wheeler