For the first fifteen years of my career, the word pension made me yawn. Classic millennial move: change jobs every couple of years, pick up a new pension pot each time, never think about any of them again. Out of sight, completely out of mind.
It was my husband who eventually sat down, made the phone calls, did the paperwork, and consolidated all five of my scattered pots into one place. This was 2017, when doing it manually was basically the only option — and it was a slog. I was lucky he did it. Most people aren't.
That's the thing. There is a pension crisis quietly building for women in this country, and a big part of it is simply not knowing what you've got or where it lives. So before we get into which SIPP is the best home for your money, let's make sure the basics are covered.
First: do you actually need a SIPP?
A SIPP (Self-Invested Personal Pension) is a pension you control yourself — you choose where it's invested, you manage it, and crucially, you can consolidate old workplace pots into it.
If you're currently employed and paying into a workplace pension, keep doing that. You're getting employer contributions on top of your own, which is essentially free money you don't want to leave on the table. What you can also do — and this is what most people don't realise — is consolidate all your old pots from previous jobs into a separate SIPP, so they're all in one place, working harder for you, with fees you've actually chosen.
One important caveat: if any of your old pensions are defined benefit (also called final salary) schemes, do not consolidate those without taking proper financial advice first. They're valuable in ways that aren't immediately obvious. For most standard defined contribution workplace pots — the kind most of us have been collecting since the 2000s — consolidating into a SIPP is a very sensible move.
Why fees matter more than you think
This is the part nobody makes interesting enough, so I'm going to try.
When you're choosing a SIPP platform, the fee structure is genuinely the most important decision you'll make. Not the interface. Not the research tools. The fee. Because over decades, a seemingly small percentage difference compounds into a very large number.
Here's what that looks like on a £200,000 portfolio growing at 6% annually over 25 years:
| Platform | Fee Structure | Annual Cost (£200k pot) | Estimated 25-year fee cost |
|---|---|---|---|
| Interactive Investor | Flat £11.99–£14.99/month | ~£144–£180 | ~£9k |
| Vanguard | 0.15% (cap £375) | ~£300 | ~£19k |
| AJ Bell | 0.25% up to £250k | ~£500 | ~£32k |
| Hargreaves Lansdown | 0.45% up to £250k | ~£900 | ~£56k |
Read that last line again. HL can cost roughly six times more than a flat-fee platform once your pot is substantial. That's not money going to work for you. It's just gone.
The reason this matters so much is that percentage-based fees scale with your pot. Which sounds fair when you're starting out and your pot is small — but as compound growth does its thing and your pension grows, so does the fee. Forever.
Flat-fee platforms flip this logic. You pay the same amount whether your pot is £50,000 or £500,000.
My top pick: Interactive Investor
I moved my own SIPP to Interactive Investor and it's where I'd point most women who are ready to take proper control of their pension.
The decision came down to fees. My pot had grown to the point where the flat fee structure genuinely nets off against what I'd be paying on a percentage platform — and once you run that maths, it's hard to unsee. I found the process of moving straightforward enough, though I'll be honest: there was still printing and posting involved. An actual envelope. In 2025. Frustrating, but unfortunately completely normal for the pension industry — it's not an II thing, it's a pensions thing.
Why II:
- Flat fee — you pay a fixed monthly amount regardless of how large your pot grows. That's the structural advantage that matters most over a long time horizon.
- Wide investment choice — funds, shares, ETFs, investment trusts. You're not limited to one provider's range.
- Platform that actually works — simple enough, clear enough, and crucially I can get into my account. That sounds like a low bar, but as you'll see below, it isn't always.
Who it suits most: If your consolidated pot is heading above £80,000–£100,000 or you're planning to build towards that, the flat fee structure starts to win materially over percentage platforms. That said, II also offers lower tiers for smaller pots, so it's worth checking the current pricing on their site.
Explore Interactive Investor's SIPP
The rest of the field
Hargreaves Lansdown
The big household name. Research tools are excellent, the education content is genuinely good, and their customer service is consistently praised. Trustpilot sits around 4.4/5.The trade-off is the fee: 0.45% on funds up to £250,000. On a large pot, that gets expensive fast. If you're newer to investing and want hand-holding and premium tools and you're okay paying for that, HL delivers. If you're cost-conscious and comfortable making your own decisions, you're overpaying.
Best for: Investors who want research, guidance, and don't mind paying for it.
AJ Bell
A solid mid-ground option. Lower than HL at 0.25% up to £250,000, with a good range of investments and a Junior SIPP if that's relevant to you. Trustpilot sits around 4.9/5 — consistently well-reviewed for customer service.The interface is sometimes described as slightly dated, but it functions well. If you want a percentage-based platform and want to pay less than HL, AJ Bell is the sensible step down.
Best for: DIY investors who want more than Vanguard's limited range but don't want to pay HL prices.
Vanguard
I've used Vanguard. The fees are genuinely low — 0.15% capped at £375 — and for passive index investing, they're hard to beat on cost at smaller pot sizes.The honest drawbacks: the platform is basic. Very basic. I also found that for various reasons I could never reliably get into my account, which is a fundamental problem when you're trying to actually manage your money. It failed on that hurdle for me. And you can only invest in Vanguard's own funds, so if you ever want to diversify beyond their range, you can't.
If you're happy with a global index tracker and want to keep things simple and cheap, that's actually a perfectly legitimate strategy. But know what you're signing up for.
Best for: Simple, low-cost passive investing. Less good if you want investment choice or actually want to be able to log in reliably.
Fidelity
A wider fund selection than Vanguard with some managed portfolio options if you want a bit of guidance built in. Fees sit at 0.35% with a cap of £90 for shares and ETFs specifically.I don't have personal experience of Fidelity's SIPP platform, so I'll leave it there rather than speculate.
What about PensionBee?
PensionBee is worth mentioning because if you have multiple scattered old pots to consolidate, they make the process remarkably easy. You give them your details, they do the chasing. For a lot of women who have been putting consolidation off for years because it feels like too much admin, PensionBee genuinely removes that barrier.
However — and this matters — their fees are percentage-based and on the higher side compared to the platforms above. That's fine as a consolidation stepping stone. Less ideal as a permanent long-term home for a growing pot. Think of it as the useful middle stage: get everything together, then consider whether you want to move it somewhere with better long-term fee structure once it's consolidated.
Quick comparison
| Platform | Fee Structure | Annual cost: £50k pot | Annual cost: £200k pot |
|---|---|---|---|
| Interactive Investor | Flat ~£12–£15/month | ~£144 | ~£144 |
| Vanguard | 0.15% (cap £375) | £75 | £300 |
| AJ Bell | 0.25% | £125 | £500 |
| Fidelity | 0.35% (cap £90 shares/ETFs) | £175 | £350+ |
| Hargreaves Lansdown | 0.45% | £225 | £900 |
Note: underlying fund fees apply on top of all platform fees above. Always check current pricing directly with the provider.
The bottom line
The best SIPP is the one you actually open and fund. That said, once you're ready to be deliberate about where your pension lives, fees are the thing to optimise for.
My own move was to Interactive Investor. Flat fee, good investment range, a platform that doesn't make me dread logging in. For anyone with a pot heading above £80–100k, or aiming to build towards that, the maths starts to make a real difference over time.
If you're starting from scratch or your pot is smaller, Vanguard's low percentage fee is hard to argue with — just go in knowing you're limited to their fund range.
And if your main challenge is still getting all your old pots in one place? Start with the consolidation. The perfect platform decision can come once you know what you've actually got.
Also on Femme Finance:
- Junior ISA & Junior SIPP: Set Your Child Up for Life
- How compound interest works — and why starting now matters
- SIPPs explained: how does a SIPP work?
This post is for informational purposes only and does not constitute financial advice. Investments can go down as well as up. Some links in this post are affiliate links — I may earn a small reward if you sign up, at no cost to you. Always consider your own circumstances or speak to a regulated financial adviser via Unbiased before making pension decisions.
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