Most people ask the wrong question. They want to know which pension is better. The real question is which one to use first, and the answer is almost always your workplace pension. But that doesn't mean a SIPP has no place in your retirement plan.
Contents
- What is a workplace pension and how does it work?
- What is a SIPP and who is it actually for?
- What does the employer match really cost you to walk away from?
- How do fees compare between a SIPP and a workplace pension?
- What is salary sacrifice and why does it change the maths?
- When does a SIPP actually beat a workplace pension?
- Can you have both a SIPP and a workplace pension?
- What do most guides get wrong about this comparison?
What is a workplace pension and how does it work?
Your employer sets it up for you. You don't have to do anything. That's by design.
Auto-enrolment, introduced under the Pensions Act 2008, means most workers over 22 earning above £10,000 a year are automatically put into a pension scheme. You're in unless you actively opt out, which most people don't.
In 2026, the minimum contributions work like this:
- You contribute at least 5% of qualifying earnings (your salary between £6,240 and £50,270)
- Your employer adds at least 3%
- The government tops this up through basic rate tax relief
Many employers pay more than the 3% minimum. Some match your own contributions up to a higher ceiling. If your employer matches 5%, you're getting a 100% return on that portion before any investment gain.
The investments inside a workplace pension are limited. You'll typically get 10 to 30 fund options: a mix of equity funds, bond funds, and a default lifestyle strategy that gradually de-risks as you approach retirement. You can't pick individual shares or investment trusts. That's the trade-off for simplicity.
Workplace pensions run through providers like Nest, The People's Pension, Aviva, Legal & General, and Scottish Widows. Your employer picks the provider and the default fund. Most people are enrolled and forget about it. That's fine in the short term. It's not a strategy for the long term.
What is a SIPP and who is it actually for?
A SIPP is a Self-Invested Personal Pension. You open one yourself, through a platform like Vanguard, Hargreaves Lansdown, AJ Bell, or Interactive Investor. You decide where to invest, and the choices are far broader: individual shares, ETFs, investment trusts, bonds, and thousands of funds from different managers.
Tax relief works the same way as a workplace pension. You contribute from your take-home pay and HMRC refunds the basic rate income tax (20%) directly into your pension. Higher rate taxpayers claim the additional 20% through self-assessment.
SIPPs work well for:
- Self-employed people who have no employer scheme
- Higher earners who've maxed the employer match and want to contribute more
- People consolidating old pensions from previous jobs
- Anyone whose workplace pension has a poor fund range or high charges
But here's what a SIPP can't do: receive employer contributions. Unless your specific employer has agreed to pay into a SIPP on your behalf (rare and requires a specific arrangement), all employer pension money stays in the workplace scheme. That's the fundamental limitation, and it matters more than most people realise.
What does the employer match really cost you to walk away from?
Here's a number worth sitting with.
Say you earn £40,000. Your qualifying earnings are roughly £33,760. If your employer matches 5% of contributions, they're adding £1,688 a year to your pension. Over 30 years, with 7% annual growth, that employer contribution alone grows to approximately £168,000.
That's money you lose entirely if you stop contributing to your workplace pension and redirect everything into a SIPP.
No SIPP can replicate this. Even the best-performing index tracker can't compensate for removing free money at source. Employer contributions are the most powerful lever available to employed pension savers, and walking away from them to gain investment flexibility is a decision that compounds into a serious shortfall.
The rule is clear: always contribute enough to get the full employer match first. Every pound above that is where the choice between your workplace pension and a SIPP becomes genuine.
If your employer matches up to 5% and you're currently contributing 3%, you're leaving 2% employer money on the table every month. Over a career, that's not a small oversight.
How do fees compare between a SIPP and a workplace pension?
This is where a SIPP can actually win, particularly as your pot grows.
Workplace pension charges are capped at 0.75% per year on default funds under FCA rules. In practice, large employer schemes often negotiate far lower. If you work for a big company, your pension might cost 0.2-0.4% per year. That's genuinely competitive.
Not all workplace pensions are cheap, though. Smaller employers often use providers charging closer to the cap, and some schemes offer only expensive actively managed funds that consistently underperform cheaper index trackers.
SIPPs let you control costs. Here's what the main platforms charge in 2026:
| Platform | Annual fee | Best for |
|---|---|---|
| Vanguard | 0.15% (capped at £375/year) | Smaller pots, index investors |
| Interactive Investor | £143.88 flat per year | Larger pots, frequent traders |
| AJ Bell | 0.25% up to £250k, then 0.10% | Mid-size and large pots |
| Hargreaves Lansdown | 0.45% on funds (capped at £45/year) | Small pots, wide fund access |
On a £15,000 pot, a workplace pension at 0.4% costs £60 a year. Vanguard's SIPP costs £22.50 plus fund charges. The gap is modest. On a £200,000 pot, the maths shifts considerably, especially with flat-fee platforms like Interactive Investor.
This is why consolidating old workplace pensions into a SIPP makes sense later in your career, not at the start. When pots are small, the fee difference is minor. When pots are large, it's meaningful.
What is salary sacrifice and why does it change the maths?
Most comparison guides skip this entirely. They compare tax relief rates and investment options, and leave it there. But salary sacrifice changes the calculation significantly, and it's only available through a workplace pension.
Here's how it works. With salary sacrifice, you agree to take a lower official salary, and your employer pays the difference straight into your pension before any tax or National Insurance is calculated. Because your salary is lower, you both save NI.
In 2026, you save NI at 8% on earnings between £12,570 and £50,270. Your employer saves 13.8% in employer NI on the same amount. Some employers pass their NI saving back to you as an extra pension contribution.
A SIPP can't do this. Tax relief at source (the standard method for personal pensions) only recovers income tax. It has no effect on National Insurance. If your employer offers salary sacrifice through the workplace scheme and you put extra money into a SIPP from your take-home pay instead, you're paying NI you didn't need to pay.
On £5,000 of annual pension contributions, salary sacrifice saves you £400 in NI compared with contributing to a SIPP from take-home pay. Over 30 years with investment growth, that difference isn't trivial.
Before deciding to top up a SIPP rather than increasing your workplace pension contributions, check whether your employer runs a salary sacrifice scheme. If they do, the workplace pension wins on tax efficiency for any contributions your employer will process that way.
When does a SIPP actually beat a workplace pension?
There are genuine situations where a SIPP is the better choice.
You're self-employed. No employer and no match. A SIPP is your primary pension vehicle. You contribute what you can, claim the tax relief, and invest as you choose. Most freelancers and contractors benefit from maxing their SIPP contributions before considering other investment wrappers.
Your workplace pension charges close to the 0.75% cap with a poor fund range. If your employer uses a scheme where you get a handful of expensive active funds charging 0.65% per year, a SIPP with cheap index funds at around 0.20% total cost will outperform on fees alone over 20-30 years. Still contribute enough to the workplace scheme to get the employer match. But redirect anything above that.
You want investments your workplace scheme doesn't offer. Some people want global index trackers, investment trusts, or specific ethical funds that simply aren't available in their employer's fund list. A SIPP gives access to the full market.
You're consolidating multiple old pensions. Leaving small pots scattered across six previous employers means six fee structures, six annual statements, and a fragmented view of your retirement. A SIPP lets you pull them into one place.
You've captured the employer match and want more control over additional savings. Once you're getting every penny your employer will match, there's no cost to using a SIPP for further contributions.
Can you have both a SIPP and a workplace pension?
Yes. For most employed people, having both is the sensible answer.
The annual allowance in 2026/27 is £60,000 (or 100% of your earnings, whichever is lower). This covers all pension contributions combined, including employer contributions. You're not restricted to one type of pension.
The practical approach for most people:
- Contribute enough to your workplace pension to get the full employer match
- Use salary sacrifice if your employer offers it
- Once the employer match is fully captured, direct additional contributions to a SIPP if you want cheaper index funds or wider investment choice
- Consolidate old defined contribution pensions into the SIPP as you accumulate them from previous employers
One important check: defined benefit schemes (final salary pensions) have built-in guarantees you'd lose on transfer. If you're in a defined benefit scheme worth more than £30,000, you're legally required to take regulated financial advice before transferring. For most people on standard defined contribution workplace pensions, SIPP transfers are a clean, well-documented process.
What do most guides get wrong about this comparison?
They treat it as a decision you make once and stick with.
It isn't. Your pension strategy should shift as your pot grows, as you change employers, and as your needs evolve. Someone at 25 with a small pot and a generous employer match should weight the workplace pension heavily. Someone at 50 with a large accumulated pot and a mediocre scheme might benefit from consolidating into a lower-cost SIPP.
The second mistake is putting investment choice at the centre of the comparison. For most people, a global index fund in a decent workplace pension performs as well as anything in a SIPP. Investment choice only matters if you know how to use it. A SIPP full of poorly chosen active funds will underperform a cheap workplace default every time.
Third: ignoring salary sacrifice entirely. If your employer runs it and you're redirecting contributions to a SIPP from take-home pay instead, you're paying National Insurance you didn't need to pay. That's not a philosophical point. It's a real cost that compounds year on year.
The answer to "SIPP or workplace pension?" is almost always: workplace pension first, up to the employer match. Use salary sacrifice if it's available. Then consider a SIPP for anything above that. Most people don't need to choose between them. They need to use them in the right order.
The winner isn't a SIPP or a workplace pension. It's using them in the right order. Start with your workplace pension, capture every penny of employer match, and make the most of salary sacrifice if your employer offers it. Once that's locked in, a SIPP gives you the investment freedom and consolidation options that workplace pensions can't. Most people don't need to choose between them. They need both, and they need to know which one comes first.