The reason fees matter is mathematical: a 1% all-in cost difference compounds into something close to a third less wealth across thirty years (a finding consistent with the FCA’s Asset Management Market Study). The reason fees confuse people is that they are paid in three different places to three different counterparties, and platforms are not always transparent about which is which.
This article maps every cost you might pay on a UK stocks and shares ISA in 2026—and which ones are worth caring about, given the size of your portfolio and how you invest.
The three layers of cost
| Layer | Charged by | Typical range | Notes |
|---|---|---|---|
| Platform fee | Your ISA provider | 0% – 0.45% | Or flat-fee, £4.99–£21.99/month |
| Fund / ETF charge (OCF) | Fund manager | 0.05% – 1.00% | Index funds at the bottom; active funds higher |
| Trading and FX costs | Platform / market maker | 0% – 0.75%+ | Sometimes invisible in the headline pricing |
A “low-cost” portfolio sits at roughly 0.20–0.40% all-in. A “high-cost” portfolio with active management can reach 1.5%+ before you even start trading.
Platform fees in detail
The platform fee is what your broker charges to hold the wrapper, execute your buys and sells, and keep your records.
In the UK retail space there are two main models in 2026.
Percentage-based platform fees
A percentage of your portfolio per year, usually billed monthly.
| Platform | Headline fee | Cap |
|---|---|---|
| Vanguard Investor | 0.15% | £375/year |
| AJ Bell | 0.25% on funds | £42/year on shares ISA |
| Hargreaves Lansdown | 0.45% on funds | £45/year on ETFs |
| Moneybox | 0.45% + £1/month | None |
Strengths: predictable, scales with portfolio size, fair for smaller accounts.
Weaknesses: at £100,000+ you are paying £450/year on Hargreaves Lansdown for what is essentially the same service a flat-fee platform offers for £144/year.
Flat-fee subscriptions
A fixed monthly charge regardless of portfolio size.
| Platform | Tier | Monthly cost |
|---|---|---|
| Interactive Investor | Investor Essentials (under £50k) | £4.99 |
| Interactive Investor | Investor | £11.99 |
| Interactive Investor | Super Investor | £21.99 |
| Charles Stanley Direct | Standard | 0.30% (percentage) |
Above £50,000–£75,000, the flat fee is almost always cheaper than the percentage equivalents.
Zero-fee platforms
InvestEngine (DIY) and Trading 212 charge no platform fee on ISAs. They make money on currency conversion (Trading 212) or on a “Managed” tier (InvestEngine).
Free is genuinely free for ETF investors who only buy GBP-denominated funds. The trade-offs are limited customer service and a narrower product range—not nothing, but not always relevant for an investor with one global tracker on a standing order.
Fund and ETF charges (the OCF)
Every fund publishes an Ongoing Charges Figure (OCF)—the annual cost of running the fund, expressed as a percentage of your holding. It includes:
- The manager’s fee.
- Custodian and administration costs.
- Audit and legal costs.
It does not include:
- Trading costs incurred inside the fund (estimated separately as “transaction costs”).
- Performance fees—rare in retail funds.
- Initial or exit charges—rare in modern funds, common on legacy retail funds.
Indicative OCFs in 2026:
| Fund type | Typical OCF |
|---|---|
| Global index fund | 0.10% – 0.25% |
| Bond index fund | 0.07% – 0.20% |
| Specialist/sector ETF | 0.30% – 0.75% |
| Global active fund | 0.60% – 1.20% |
| Multi-asset “managed” fund | 0.40% – 0.85% |
The OCF is deducted continuously inside the fund—you never see it on a bill. The only place it shows up is in the relative performance versus the index over time.
Trading and FX costs
The third layer.
Trading commissions
- Most UK platforms charge £0 for fund trades.
- Share and ETF trades are free on Trading 212 and InvestEngine; £5–£12 elsewhere.
For a regular monthly investor in funds, trading costs are usually zero.
Foreign exchange (FX) costs
If you buy a US-listed ETF, your platform converts GBP to USD. The “spread” they charge on this conversion can be significant:
| Platform | FX spread |
|---|---|
| Trading 212 | 0.15% |
| Interactive Investor | 1.5% (£100k+ portfolio: tiered down) |
| Hargreaves Lansdown | 1.0% |
| AJ Bell | 0.50%–1.00% |
A 1% FX cost on a £10,000 trade is £100. If you are buying US ETFs regularly, FX spreads can be one of your largest costs—and they do not appear on the front page of any platform’s pricing.
Bid-offer spreads inside the fund
When you buy or sell an ETF, the price difference between the bid and the offer is a small implicit cost. For mainstream funds it is negligible. For thinly-traded niche ETFs it can be 0.20%+, which compounds against any thesis you had for buying them.
Exit fees and transfer-out costs
A handful of platforms still charge per-line transfer-out fees:
| Platform | Exit fee |
|---|---|
| Interactive Investor | £0 since 2022 |
| Hargreaves Lansdown | £0 since 2021 |
| AJ Bell | £0 |
| Some legacy fund supermarkets | £25 per holding line |
Always check the destination platform’s transfer cashback offers—they often more than offset any exit cost, sometimes by an order of magnitude.
Adding it up: realistic 2026 costs
A worked example. £20,000 in a stocks and shares ISA, holding HSBC FTSE All-World Index (OCF 0.13%):
| Platform | Platform fee | Fund OCF | Total annual |
|---|---|---|---|
| Vanguard Investor (different fund - FTSE Global All Cap) | £30 | £46 | £76 |
| AJ Bell | £50 | £26 | £76 |
| HL | £90 | £26 | £116 |
| Interactive Investor (Essentials) | £60 | £26 | £86 |
| InvestEngine (DIY ETF) | £0 | £26 (on iShares World ETF) | £26 |
For a £20,000 ISA the spread between the cheapest and the most expensive is £90/year. Compounded over thirty years, that is a meaningful pot all by itself.
For a £200,000 ISA the spread blows out:
| Platform | Annual cost |
|---|---|
| Vanguard Investor | £375 (capped) + fund OCF |
| Interactive Investor (Investor) | £144 + fund OCF |
| Hargreaves Lansdown | £900 + fund OCF |
Which is why platform choice scales with portfolio size, not the other way round.
Hidden or under-disclosed costs
A short list of fees that are real but rarely front-page:
- Custody charges on individual share holdings (mostly absorbed into platform fees in 2026, but check).
- Dilution levies on inflows/outflows of certain funds (rare on indexers).
- Stamp duty at 0.5% on UK share purchases (does not apply to ETFs, OEICs or unit trusts).
- PTM (Panel on Takeovers and Mergers) levy of £1 per £10,000 trade on UK shares.
For a typical fund-only ISA portfolio, none of these apply.
What to actually do
If your goal is a low-cost stocks and shares ISA in 2026:
- Pick a global index fund with an OCF around 0.13–0.25%.
- Pick a platform that, given your portfolio size, costs less than 0.25% on the platform fee alone.
- Avoid platforms with material FX spreads if you are buying US-listed ETFs.
- Reassess platform choice when your portfolio crosses £75,000.
A reasonable end-state for a £50,000+ portfolio in 2026: total costs around 0.30–0.40% per year. If you are materially above that, something is off—usually an active fund or a legacy platform that has quietly drifted out of best-buy territory.
The savings, compounded for thirty years, are larger than they sound.
Frequently asked questions
- How much do stocks and shares ISA fees typically cost?
A reasonable target for a UK stocks and shares ISA in 2026 is total costs of 0.25–0.45% per year, combining platform and fund charges. ISAs charging more than 1% all-in are usually paying for active management or premium service most readers don't actually need.
- Are flat-fee ISAs worth it?
Above £75,000–£100,000 invested, a flat-fee platform like Interactive Investor usually beats a percentage-fee equivalent on cost. Below that, percentage-fee platforms with low caps are usually cheaper—and the crossover point is what most people miss.
- What is a fund OCF?
Ongoing Charges Figure—the annual cost of owning the fund, including the manager's fee and operational costs. It excludes trading costs inside the fund and any front-end loads. UK index funds sit at 0.05–0.25%; active funds 0.5–1.0%+.
