Pension or ISA: what does each do with the same pound?

Taxed at opposite ends

A pension contribution gets income tax relief at the rate you pay, so a pound of pay before tax is a pound in the pot. Inside the pot it grows free of tax. What comes out is taxed as income, apart from the tax-free part.

Money paid into an ISA has already been taxed as pay. Inside, interest, dividends and gains are free of tax, and nothing is taxed on the way out.

If the rate of tax is the same at both ends, the two come out level, however much they grow. Take a basic-rate taxpayer in England, Wales or Northern Ireland and £100 of pay before tax:

Growth would raise every row by the same share, so the gap stays the same after thirty years. The pension comes out ahead here because of one rule, the tax-free part. The other rules that set the two apart are below.

What a pension adds

• A tax-free part. Up to 25% of a pension can be taken free of income tax, to a limit of £268,275 across all your pensions.
• An employer’s money. Under automatic enrolment a workplace scheme takes at least 8% of qualifying earnings, of which the employer pays at least 3%, on earnings between £6,240 and £50,270 a year. That money exists only inside the pension, and many employers pay more than the minimum.
• Relief without earnings. Someone with no earnings in a year can still have relief on contributions up to £3,600 gross.
• National Insurance, through salary sacrifice. Where an employer offers it, pay given up for a pension contribution escapes National Insurance as well as income tax. For most earners that is 8% on the employee’s side, and the employer saves its own contribution too.
• Tax at the other end at a lower rate, often. Retirement income meets the same bands as pay, and many people are in a lower band then than while they worked.

The government has said that from 6 April 2029 National Insurance will be charged on sacrificed pension contributions above £2,000 a year. That is announced, not yet law.

The full rate of the new State Pension is £241.30 a week, from 6 April 2026.

The personal allowance is £12,570 a year, and the full new State Pension takes up most of it. So pension income above the State Pension meets tax from close to its first pound, at whichever band that income reaches.

What an ISA keeps open

• Access at any time. Money can be taken out of an ISA whenever its terms allow, with no tax and no effect on anything else. In a flexible ISA it can go back in during the same tax year without using the allowance again.
• A bridge before a pension can be drawn. Most pensions cannot be drawn before 55, rising to 57 on 6 April 2028. Someone who stops work earlier lives until then on what sits outside a pension, which the Home stretch calls the bridge.
• Pension contributions untouched. Drawing taxable money from a pension flexibly cuts what can be paid into pensions afterwards to £10,000 a year, the money purchase annual allowance. Drawing from an ISA changes nothing.
• Outside the tax bands. Money taken from an ISA is not income for tax, so it sits outside the bands that pension withdrawals and the State Pension fill.

The yearly limits

The pension allowance tapers for the highest earners, once threshold income passes £200,000 and adjusted income passes £260,000. Relief is also limited to the year’s earnings. The Home stretch lists the room left under each allowance before the tax year ends.

Rules that are changing, on both sides

• Inheritance tax. From 6 April 2027 most pension money left unspent at death counts towards the estate. An ISA has always counted.
• The minimum pension age. It rises to 57 on 6 April 2028. An ISA has no age.
• Cash ISAs. From 6 April 2027 the cash part of the allowance is capped at £12,000 for anyone aged 64 or under at the end of the tax year.
• Salary sacrifice. From 6 April 2029, if the announced change becomes law, National Insurance applies to sacrificed contributions above £2,000 a year.

Each of these moved the balance a little, and more will. A change to pension rules lands on money that cannot be taken out until the age the rules set. A change to ISA rules lands on money that can be taken out at any time. This guide states the position as it stood when the guide was written, with its figures read again on the date at the top.

Even with the changes above, a pension still brings an employer’s money, which no other wrapper receives, and a tax-free share of what comes out. Inside a stocks and shares ISA, interest, dividends and gains are untaxed, where interest in an ordinary savings account can be taxed. Like a pension, a stocks and shares ISA rises and falls with the investments it holds. Unlike a pension, it can be drawn at any age.

This guide informs. Which wrapper to use, in what order and how much turns on your own pay, employer, age and plans. MoneyHelper gives free, impartial guidance, and a regulated financial adviser can advise on your own case.

How Landfall handles it

The Home stretch offers two moves for savings outside an ISA: a payment into the pension and a top-up of the ISA. They draw on the same savings, so what one takes is not offered to the other. Either can stand alone, and the order is yours.

The bridge weighs on the choice: money in a pension cannot pay for the years before it can be drawn, while money in an ISA still can. The tab’s balance shows what the bridge needs either way.