Index funds are one of the most common ways beginners start investing. Instead of choosing individual companies, you buy a single fund that follows a whole market or a large part of it.
This guide explains how index funds work, what to compare between them and the simple steps from opening an account to making your first purchase.
Part 1
What an index fund is
An index fund aims to copy the performance of a market index, such as a list of large global companies, rather than trying to beat it.
Because it follows a set list instead of paying managers to pick shares, an index fund is usually cheaper than an actively managed fund. Many index funds are ETFs, which trade on a stock exchange.
Part 2
Choose the index first
The index decides what you own: a global index spreads you across many countries, a single-country index concentrates you.
Look at how many companies the index holds, which countries and sectors dominate it, and whether one region makes up most of it.
Part 3
Compare funds tracking the same index
Funds following the same index can still differ in cost and structure.
- Ongoing charge (often shown as TER or OCF)
- Accumulating (reinvests dividends) or distributing (pays them out)
- Fund size and how closely it has tracked its index
- Currency it trades in on your broker
Part 4
Buy through an authorised broker
Check the broker is authorised by your national regulator, then compare its trading and account fees.
In Ireland you can check firms on the Central Bank of Ireland's registers. Regular, fixed monthly amounts can make it easier to stay invested through ups and downs.
Part 5
Check the tax treatment where you live
Tax on funds and ETFs varies by country and can differ from tax on individual shares.
In Ireland, many EU-domiciled funds and ETFs are taxed differently from shares, including an exit tax and a deemed disposal rule. Rules change, so confirm current treatment on Revenue.ie or with a qualified adviser. This guide is not tax advice.
How Mesodian helps
Common questions
Are index funds good for beginners?
Many beginners use broad, low-cost index funds because they spread money across many companies in one product. They still fall when markets fall, so they suit money you can leave invested for years.
What is the difference between an index fund and an ETF?
An index fund is any fund that tracks an index. An ETF is a fund that trades on a stock exchange. Many ETFs are index funds, but not all index funds are ETFs.
How much do I need to invest in an index fund?
Many brokers let you start with small amounts or buy fractions of an ETF. Check the broker's minimums and fees, because fixed fees take a bigger share of small purchases.
Official and independent sources
- Central Bank of Ireland registers — check a firm is authorised
- Central Bank of Ireland — consumer hub
- Revenue — capital gains tax
- CCPC — investing
- Investor Compensation Company (Ireland)
- Financial Services and Pensions Ombudsman (Ireland)
- Pensions Authority (Ireland)
- ESMA — investor corner
- BaFin (Germany) — financial regulator
- AMF (France) — financial markets regulator
- AFM (Netherlands) — financial markets regulator
- FCA register (UK)
- MoneyHelper (UK) — investing
- Investor.gov — introduction to investing