The Autumn Budget is on Wednesday 28 October. Between now and then, a great deal of what you read about your pension will boil down to a single instruction: act before the rules change.

It sounds sensible. Rules do change, and getting ahead of a change has obvious appeal.

But most of what gets written in the six weeks before a Budget isn't a rule change. It's speculation about one. And the gap between those two things is exactly where people make decisions they cannot undo.

So this isn't a prediction post. I have no idea what's in the red box, and neither does anyone else writing about it. What I can do is draw a clean line between what is already confirmed and written into draft law (which you can plan around today) and what is only rumour (which you should not restructure your retirement around).

What's actually confirmed

Start with the date itself. The Chancellor, John Healey, confirmed the Budget for 28 October in a letter to the Treasury Select Committee, published on gov.uk on 31 July 2026. That's the fixed point. Everything below is already announced policy, not a forecast.

The Cash ISA limit changes on 6 April 2027

This is the freshest and most concrete of the three, so it gets the most room.

From 6 April 2027, the annual subscription limit for a Cash ISA (Individual Savings Account) falls from £20,000 to £12,000 for savers under 65. Savers aged 65 and over are not affected and keep the full £20,000 in cash.

The detail that gets lost in the headlines: the overall ISA allowance is unchanged at £20,000 for everyone. For an under-65 saver, the remaining £8,000 doesn't disappear. It has to go into an investing-type ISA instead, such as a Stocks & Shares ISA.

Where does this sit on the confirmed-to-rumour scale? Firmly at the confirmed end, with one honest caveat. The policy was set out in a government factsheet in June 2026 and carried into draft Finance Bill legislation published on 13 July 2026. A technical consultation on the draft regulations closed on 2 August 2026, and the regulations are expected to be laid in autumn 2026 ahead of the April 2027 start.

So: confirmed policy, in draft legislation, with the regulations not yet fully made. That is a very different animal from a newspaper column.

The practical consequence is simple. For the 2026/27 tax year, which runs to 5 April 2027, the full £20,000 can still go into cash. The change bites on contributions made from 6 April 2027 onward, and only for under-65s.

Unused pensions come into the estate for IHT from April 2027

From 6 April 2027, most unused pension funds and pension death benefits will count as part of the estate for Inheritance Tax (IHT), where they generally sit outside it today. The standard IHT rate above the available nil-rate bands is 40%.

This one is announced policy with a confirmed start date, and it genuinely reshapes how legacy planning interacts with drawdown decisions. We've written about it at length separately, so I'll leave it there rather than repeat the whole analysis.

Salary sacrifice National Insurance relief changes in April 2029

From April 2029, National Insurance relief on pension contributions made by salary sacrifice is removed above the first £2,000. Announced, dated, and a long way off. Also covered in its own post.

Three changes. Three known start dates. Nothing on that list requires you to guess.

What's only rumour

Now the other column, and the labels matter here.

Two things dominate pre-Budget speculation almost every year:

• Cuts to the 25% pension tax-free lump sum. Rumoured. Not announced, not legislated, not government policy.
• Changes to higher-rate pension tax relief, often framed as a move to a single flat rate. Also rumoured. Also not announced, not legislated, not government policy.

Both have been floated ahead of multiple recent Budgets. Neither has been enacted at them. That isn't a prediction that they never will be. It's a reminder of how weak the evidential base is when you're asked to restructure a pension around a headline.

As things stand for 2026/27, the rules are what they've been: normally 25% of a pension can be taken tax-free, subject to the Lump Sum Allowance of £268,275 across all pensions, and contributions attract tax relief at your marginal rate.

Those are the numbers to plan with, because those are the numbers that exist.

Why acting on a rumour can cost more than the rumour

Here's the part I actually care about, and it's the reason this post exists.

A confirmed change gives you a date and a known end state. You can model it. A rumour gives you neither, and the actions people take in response to rumours tend to be one-way doors.

Take the most common one. Imagine a 57-year-old with a £400,000 SIPP (Self-Invested Personal Pension) who reads that the tax-free lump sum might be cut, and decides to take £100,000 out now to "lock it in" before 28 October.

Look at what that actually does.

• It cannot be reversed. Once that money is out of the pension, it's out. You can't put £100,000 back in. The ISA allowance is £20,000 a year, so rebuilding a tax-free wrapper around it takes years, and the pension annual allowance has its own limits and tapers.
• It changes how the money is taxed from that day forward. Inside the pension, growth is sheltered. Sitting in a general investment account or a savings account, interest and gains become taxable beyond the Personal Savings Allowance, the £500 dividend allowance and the £3,000 capital gains exempt amount.
• It exposes the money to market risk on a timetable set by a headline, not by you. Wherever it's reinvested, investments can fall as well as rise, and you've now compressed that decision into a few weeks.
• It can trip the MPAA. If the withdrawal is taken as taxable income from a flexible pension rather than purely as tax-free cash, it triggers the Money Purchase Annual Allowance, cutting what you can contribute with tax relief from £60,000 a year to £10,000. For someone still earning and still contributing, that's a permanent handbrake. We've covered the MPAA mechanics in their own post.
• It scrambles your sequencing. £100,000 of extra cash outside the wrappers changes which pot you should draw first for the next decade, which changes your taxable income in every one of those years.

None of that means taking tax-free cash is a bad idea. For plenty of people, at the right point in a plan, it's the right move for entirely sound reasons. Providers and commentators have repeatedly warned that the speculation cycle itself causes savers real harm, and that's the point: the problem isn't the decision, it's making the decision for the wrong reason, on a deadline invented by someone else.

A change you can see coming, with a date attached, can be planned for calmly. A change that may never happen cannot be planned for at all.

What holds up whatever lands on 28 October

So what do you do between now and then? Mostly, know your own numbers well enough that a Budget becomes an input rather than an emergency.

Three things hold their value regardless of the outcome.

Use the allowances that already exist

The £20,000 ISA allowance for 2026/27 is real and available now. Pension tax relief at your marginal rate is real and available now (income tax rates and bands differ in Scotland, so check which set applies to you). Allowances that lapse at tax-year-end on 5 April are a use-it-or-lose-it question that has nothing to do with the Budget.

Know your withdrawal order before you need it

The order you draw from a SIPP, a workplace pension, ISAs and a general investment account, and when you start the State Pension, drives your taxable income in every retirement year. That's where most of the recoverable tax sits, and it's entirely within your control. Optiml UK is being built to sequence exactly that: which pot, in what order, to lower tax across the whole horizon rather than a single year.

Keep the plan flexible enough to absorb a change

A plan that only works under one set of rules isn't a plan, it's a bet. The useful question isn't "what will the Chancellor do," it's "if the rules moved in this direction, what would my plan do about it, and how much would it matter?"

That's the question Optiml UK is designed to answer. When it launches, you'll be able to model a change and see the lifetime impact in seconds instead of arguing with a spreadsheet, and compare two versions of your plan side by side. Confirmed items like the April 2027 pension-IHT change get built into the modelling because they have a date. Rumours don't, and shouldn't.

The honest position on 16 September is that we don't know what's coming on 28 October. We do know the three changes above are already in motion, and that's plenty to be getting on with.

After the Budget

We'll write up what actually lands once it lands, on 28 October, with the real detail and the real dates rather than the run-up noise. Confirmed changes get modelled. Speculation gets left where it belongs.

Until then, the calmest thing you can do is also the most useful: understand your own numbers, use the allowances you've already got, and resist any deadline you didn't set yourself. If a change does come, the people who know their plan will adjust it in an afternoon. Where a decision is genuinely finely balanced, that's what professional advice is for.

Optiml is coming to the UK, and this is precisely the kind of decision we're building it to handle.

It's not about predicting the Budget. It's about not needing to.