Rachael from Accounts – Taxing Your Tax-Free ISA accounts

Another Sunday. Another portfolio push over the final week in May, what a month!

The AI train kept barrelling on this week, same as last — and that foreboding I mentioned hasn’t gone away. The trims of my biggest positions feel like one of those memes: the little car sneaks onto the tracks, and the train just ploughs straight on through.

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So in trying to get ahead of it, I’ve left potential profits on the table — but parked some fear, too. Which one I’d rather sit with on a Sunday is a toss-up I’m still working through. I trimmed my own runaway gain train this week again, as surely no higher? I also cut loose one small loser, and let the cash build — 16% at one point, a high for the year. Of course, I couldn’t just sit on it, I redeployed around 5% into an old favourite I liked the look of at its new more attractive price.

I didn’t write last week’s piece for an audience. I wrote it to speak to “my book” out loud — to the swells that have carried me this far. If I’m ever going to reach Valhalla, I need to be honest about what’s behind me, and learn to keep the boat facing forward more often than not.

And speaking of navigating through unknown waters — the X algorithm decided to throw me a bone this week. Coincidence? I doubt it. Since the opening post last week, my feed has exploded with UK ISA investors.

Honestly, I’ve never seen so many pop up at once. All on different journeys, in it for different reasons — but circling the same patch of ground. That one tax-free place left standing in the ever more over-taxed British Isles.

I doubt more than a handful have glimpsed my page so far. But it feels, for the first time in a long while, like the water’s got more boats tacking through the wind than just mine — hopefully, with this and my 12-week blogging commitment, I can make it out of the doldrums!

So onto the topic of this weeks blog, ISA investing, specifically the upcoming 2027 rule changes and that the Eye of Mordor, or, as some would call it, Number 11 Downing Street has now fixated on. Our chancellor, forever friendly to entrepreneurs, businesses and private individuals trying to better themselves, has turned her gaze on that one tax-free corner too. So what’s Rachael from Accounts actually planning to change in our S&S ISAs — and should we be worried?

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Right. Let’s separate what’s actually law from what’s still a rumour in a nice suit.

Three different things are going on here, and the internet has blended them into one big scary blob. Pull them apart and it gets a lot less frightening. Mostly.

One — and this is law, signed and dated. From 6 April 2027, the cash ISA allowance drops from £20,000 to £12,000. But only if you’re under 65; hit 65 and you keep the full 20 stacks. Your total ISA allowance is still £20,000 — it’s just the cash-only slice that gets capped. The other £8,000 can go into stocks and shares or a Lifetime ISA – How the interest on this cash will be taxed when in that ISA is still unclear.

Two — also law. Tax on interest earned outside an ISA goes up two points across the board from the same date: 20 to 22%, 40 to 42%, 45 to 47%.

And then there’s the third thing. The one in large font on a lot of the headlines and financial commentators.

Three - HMRC has signalled — in a post-Budget newsletter, so this isn’t pub talk — that it intends to tax the interest earned on cash held inside a stocks and shares ISA to close the potential loop hole of £12,000 in the cash ISA and £8000 in the S&S not invested.

But here’s what matters: it isn’t law yet. It’s a proposal. HMRC’s own line is that industry will be “consulted on the draft legislation.” The platforms are reportedly tearing their hair out, nobody’s sure how it’ll work, and April 2027 is coming fast. So treat the likely closure of loophole as unconfirmed for now, but likely

One genuine bit of comfort in all this: whatever lands, the money already in your ISAs is safe. None of it is touched. This is about what changes from April 2027 onwards, not what you hold today – BUT what happens when you sell a stock and it becomes cash is that classed as a new cash entry?

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So that’s the what. The question I actually want to chew on is the why. So why’s everyone shouting? Why this lever, why now? Because three groups want three different things from your money — and you’re the rope in the tug of war.

In the first corner: the Treasury. They want two things, and they’re honest about one of them. They want an investing culture — more of us in the market, fewer of us sat on cash doing nothing. There’s a fair argument buried in there: the research reckons the habitual cash-hoarder quietly gives up a couple of percent a year to inflation and missed growth. And there’s a quieter win for the Treasury too. Money that moves gets taxed on the way — stamp duty when you buy the shares and plenty of other taxes if you were ever to dare to make a profit and cash I tout to spend. Stagnant cash in a tax-free wrapper does none of that. A nation that invests is a nation the Exchequer can clip a coin from at every step.

In the second corner: the building societies. They want your cash, and not for sinister reasons. Your cash ISA is what they lend back out as mortgages. Cut the inflows, they warn, and home loans get pricier. They hold something like 46% of all cash ISA balances — north of £200bn — so they’re not a small voice. The brokers, naturally, call the mortgage warning scaremongering.

In the third corner — and this is the one nobody mentions: the investment platforms. The brokers. The very people running adverts about taking control of your future. They didn’t just support the cash ISA cut; some wanted it deeper. Ten grand. Scrapped entirely. Because every pound you shift out of cash and into stocks is a pound they clip a fee on. Funny, that — their share prices jumped the day the cut was announced. Mr Market, for once, read the room perfectly, he saw exactly whose pockets this fills.

So when you read a hot take in the coming months telling you exactly what to do with your ISA, ask one question first: what’s their book? The broker wants you invested. The building society wants you in cash. The Treasury wants you in British equity. Everyone in the room is talking up their own position and none are focused on what’s best for the average British saver or investor.

The direction is set. The detail is still being argued over. And if the last few governments are anything to go by, we already know roughly how the cookie crumbles: nothing that actually helps the saver, and a fresh layer of bureaucracy on top

So what am I doing about it? Not to much to be honest, we’ve got one tax year left at the full £20k cash allowance before it drops to twelve and I havent filled a cash ISA, well ever so as usual I’ll use it only if cash is the right tool, keep the S&S ISA invested rather than parked, and reassess in April 2027 when the rules actually exist.

If you made it this far — thank you. As always: take what’s useful, ignore what’s not, and come find me for a chat on X @compound_coach_

Next Sunday: household cash is on fire, and no one’s listening to the alarms.

Let’s talk soon,

Matt,

TheCompoundCoach

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