Best SIPP UK 2026: 10 Providers Compared

The best SIPP in the UK for 2026 is the one whose fee model fits your pot size and how you invest - there is no single winner. A SIPP (self-invested personal pension, a do-it-yourself pension wrapper you control) charges two layers of cost: a platform fee to the provider and an ongoing charge (OCF, the annual cost of the fund itself) to the fund manager. Get the platform fee wrong and you can hand over hundreds of pounds a year for nothing.

This guide compares ten of the most popular UK SIPP providers on their 2026 charges, and pairs naturally with our Vanguard vs InvestEngine comparison. Contributions attract tax relief at your marginal rate, and the 2025/26 annual allowance is £60,000, as set out in the gov.uk pension tax rules.

This comparison is based on each provider's published 2026 fee schedule and independent broker-fee tables, not on personal use of every account. We focus on the platform/custody fee (the charge for holding the account), dealing costs for funds and shares, account minimums, the available investment range, and whether the provider offers flexi-access drawdown. Fund OCFs are extra and depend on what you buy.

It depends entirely on pot size and investments. For a portfolio built only from exchange-traded funds, InvestEngine's £0 platform fee is unbeatable. For a typical mixed portfolio under about £80,000, AJ Bell's capped 0.25% and Vanguard's 0.15% are hard to beat. Above roughly £100,000, interactive investor's flat fee pulls clearly ahead. The table below shows the platform fee alone on a £50,000 pot - fund charges are extra.

This is the single most important decision. Percentage-fee platforms (Vanguard, AJ Bell, Fidelity, Hargreaves Lansdown) charge a slice of your pot, so they are cheap when the pot is small but grow more expensive as it builds. Flat-fee platforms, chiefly interactive investor, charge the same amount whatever your balance.

The crossover sits at roughly £80,000 to £100,000 for capped-percentage rivals. Below it, a percentage fee usually wins; above it, a flat fee saves more every year your pot grows. On a £250,000 SIPP, interactive investor's roughly £180 a year compares with several hundred pounds on a percentage platform.

Most transfers are started from the new provider's side: you open the SIPP, complete a transfer request naming your old pension, and the provider handles the rest, usually electronically within a few weeks. Cash transfers are simplest; an in-specie transfer moves your existing investments without selling them.

Before moving, check three things: whether the old scheme charges an exit fee, whether you would lose any valuable guarantees (such as a guaranteed annuity rate or protected pension age), and whether a defined-benefit pension is involved, in which case regulated advice is legally required above £30,000. The government-backed MoneyHelper service explains the safeguards.

Further reading: gov.uk - Tax on your private pension contributions, MoneyHelper - Pensions and retirement. Provider fees were checked against each platform's published 2026 charges and independent broker-fee tables in June 2026.