Active and passive funds: compare the job, costs and evidence
An active fund uses a manager's decisions to pursue its investment objective. A passive or index-tracking fund aims to follow a specified market index or rules-based exposure. Neither label tells you, by itself, whether the fund fits your goals or how much risk it takes.
Start by comparing the investment objective and market exposure. A low-cost fund following the wrong market can be unsuitable, while a higher-cost active fund needs a clear explanation of the work and outcome being sought.
Understand what each approach is trying to do
An index tracker seeks to follow a specified index, subject to costs and tracking differences. An active manager makes choices within the fund's mandate, which may aim to outperform a benchmark or pursue another stated objective.
Vanguard's explanations distinguish these approaches and their objectives. They describe mechanisms; they do not establish that a particular fund will outperform in the future. Vanguard: index-tracking funds and active funds.
Read the actual mandate. Some active strategies are tightly constrained, while different indices can produce very different portfolios. The broad label should be the start of the comparison, not its conclusion.
Match the exposure before judging performance
A global equity tracker and an active fund investing in smaller UK companies do not offer the same exposure. A difference in returns may reflect the markets involved rather than the benefit of active or passive management.
Compare the assets, regions, company sizes, sectors and other material characteristics. Where the portfolios differ deliberately, ask why that difference is useful within your overall plan.
The same care applies to risk. A fund that outperformed during one period may have held more concentrated or volatile investments. A result should be understood alongside the risks taken to produce it.
Convert the fee difference into pounds
Suppose two fictional funds have annual ongoing charges of 0.20% and 0.80%, applied to an assumed constant £100,000 holding. The simplified annual amounts are £200 and £800, a £600 difference before any other costs.
The higher-cost fund would need enough additional gross performance to overcome that cost difference if all other relevant features were equal. But all other features may not be equal, and future performance is uncertain. The example is not evidence that either fictional fund is preferable.
Include platform, trading, currency and advice charges separately where relevant. An ongoing charges figure is useful, but it should not be mistaken for every cost the investor incurs.
Read performance on a consistent basis
Use the same dates, currency and treatment of distributions. Establish whether fund charges have been deducted. A gross manager return should not be compared with another fund's net investor result without adjustment.
Consider how the fund behaved through different conditions rather than selecting only a recent favourable period. Check whether the manager, mandate or team changed during the history being shown.
For a tracker, ask about the difference between its outcome and the index it follows. For an active fund, ask what explains the result and whether the stated approach remains the same. Neither question requires assuming that past results will repeat.
Look at the combined portfolio
Active and passive funds can overlap in their holdings. Combining both does not automatically create diversification if each is heavily exposed to the same companies or market segment.
Similarly, owning several trackers can concentrate the portfolio if their indices overlap. Review the underlying exposures across pensions and investment accounts, including any employer shares held separately.
Ask which role each fund plays. If two funds do almost the same job, there should be a reason for holding both beyond the fact that one is active and one is passive.
Agree a review process before changing funds
A fund should not be judged solely by whether it led a performance table this year. Agree what would prompt review: a change in your needs, a material mandate change, unexplained behaviour, costs or a persistent failure to do the job expected of it.
Switching can involve dealing costs, time out of the market and tax consequences outside relevant wrappers. Those effects belong in the decision, even when the proposed replacement has a lower headline charge.
If an adviser recommends an active fund, ask what it adds after costs and why it is appropriate. If the recommendation is passive, ask why the chosen index and portfolio mix fit the goal. The answer should be specific enough to understand without relying on a general claim that one investment philosophy is always superior.
Related reading
Sources and context
General educational information, not personal financial advice. Examples are illustrative unless identified as recorded evidence.
Sources checked 18 September 2026. Our editorial standards.