Is OneFamily's ISA good value when my child's CTF matures?
09 March 2026
Question by Rob
My son is turning 18 and his Child Trust Fund with OneFamily is maturing. How does their ISA compare to other providers?
Answered by Boring Money
When a CTF matures, your son can either withdraw the money or roll it into an adult ISA, and it's well worth shopping around before defaulting to the provider he's already with.
OneFamily do offer an adult Stocks & Shares ISA, but we don't currently include them in our independent reviews, so we can't give you a head-to-head comparison based on our own testing. What we can tell you is that at 1.1% their headline charge sits on the expensive side compared to much of the market, particularly for a pot that's likely to grow over time.
To give you a sense of what's available at a more competitive price point, here's how the market looks for ready-made ISA options:
Provider | Approx. total annual cost |
IG Smart Portfolios | ~0.22–0.72%* |
InvestEngine | ~0.44% |
Bestinvest | ~0.49–0.64% |
Moneyfarm | ~0.40–1.05% |
Monzo | ~0.30–0.90% |
Natwest Invest | 0.62% |
Moneybox | ~0.57–1.08% + £12/yr |
Wealthify | ~0.75–1.18% |
Octopus Money Direct | ~0.83% |
JP Morgan | ~0.65–1.18% |
Plum | ~0.51–1.51% + £48/yr |
Approx. total annual cost includes platform fee, underlying fund charges, and transaction costs where disclosed.
Source: Boring Money Insights, OIR 2026. Charges shown cover a range of portfolio types and investment options available from each provider. Figures are correct as at 1 March 2026 and are subject to change. Always check the latest fees directly with the provider before investing.
To put those fees into real pounds and pence, here's what our three lowest-cost providers would charge on ready-made solutions at different portfolio sizes:
Provider | £1,000 | £5,000 | £10,000 | £20,000 |
Bestinvest | £5.6 | £28 | £56 | £112 |
Freetrade | £2.7 | £13.5 | £27 | £54 |
Interactive Investor | £73.48 | £79.88 | £87.88 | £103.88 |
Monzo | £3.90 | £19.50 | £39.00 | £78.00 |
Source: Boring Money Insights, OIR 2026. Charges shown cover a range of portfolio types and investment options available from each provider. Figures are correct as at 1 March 2026 and are subject to change. Always check the latest fees directly with the provider before investing.
Head to our ISA comparison table to see the full market and read what real customers think.
