Interactive Investor

ISA charges over time - how we worked it out

We partnered with independent experts at The Lang Cat to develop the value comparisons. We used the following criteria to find out how investing in an ISA with ii's fair flat fees compares with other providers.

Same ISA, lower cost

Analysis of charges and impact on portfolio values

Our analysis compares the potential impact of ongoing administration fees and trading charges for the following Stocks & Shares ISAs on returns over a 30 year period, based on an individual with the profile described below. We assumed that investment charges, rates of investment growth and rates of inflation were the same across the board. The examples are not illustrations of what you might get back. This will always depend on your personal circumstances.  Investment returns go down as well as up and you may get back more or less than any figure illustrated.

Total ISA value after 30 years


Total Portfolio Value

Difference vs ii

Interactive Investor (Investor plan)



Hargreaves Lansdown



AJ Bell YouInvest



Fidelity Personal Investing



Barclays Smart Investor



Total charges after 30 years


Total Charges

Difference vs ii

Interactive Investor (Investor plan)



Hargreaves Lansdown



AJ Bell YouInvest



Fidelity Personal Investing



Barclays Smart Investor



Typical investor ISA

For all example comparisons, our analysis assumes:

  • A typical investor aged 35 with an accumulated ISA value of £50,000
  • Over a 30 year investment lifecycle, annual gross subscriptions of £10,000 have been added to the ISA
  • One buy and one sell trade in each year, with associated dealing charges included.
  • Equal split in funds (Open Ended Investment Companies) and shares.

The investment returns reflect the following charges:

  • Administration fees
  • Dealing costs (assuming online transactions only)
  • Fund manager charges, known as the Ongoing Charges Figure.

All competitor charges were taken from their published fees correct as at 1 September 2022. In the summary tables above, charges and portfolio values have been rounded to the nearest £100 for illustration purposes.

Ongoing Charges Figure (OCF)

  • The analysis assumes a typical portfolio of active funds, with an average OCF of 0.66%.
  • This OCF is taken from the investment each year, not from your ISA.
  • The typical OCF used is the average fee charged by the active funds (not investment trusts) making up the ii Super 60 range, as published in their Key Investor Information Documents in October 2020. Each provider shown may offer a different range of investments.

Investment returns

For all comparisons shown, the Lang Cat assumed:

  • Future investment growth will be at 5%. This is for illustration only and is not guaranteed. Investment returns can go down as well as up.
  • An inflation rate of 2.00% throughout the period. Inflation is applied to regular contributions and to instances of fixed fees, but not used to adjust final projected values.