https://www.investopedia.com/ask/answers/033015/whats-difference-between-index-fund-and-etf.asp
Index Mutual Funds vs Exchange-Traded Funds: Which Option is Best for You? When I’m advising clients, I have to be ready to answer any questions they have about investment options. With so many different types of vehicles out there, I need to stay vigilant in keeping up my knowledge and expertise. Luckily, this is the kind of thing I’m passionate about, and my clients have learned that it’s very hard to stump me with financial questions. One of the questions I frequently receive is about the relative advantages of index mutual funds vs. exchange-traded funds, or ETFs. They both offer diversity and are great long-term investments. The big difference between them, from a trading perspective, is that ETFs can be bought and sold throughout the trading day, while index funds are only priced at the end of the day, when price points are set. Here are some of the key differences in their structure: Index Funds Index funds are a type of mutual fund that aims to replicate the performance of a specific market index, such as the S&P 500 or the Dow Jones Industrial Average, rather than trying to outperform it. The goal is to match the returns of the chosen index by holding the same stocks or securities in similar proportions. Index funds have low turnover rates since they typically buy and hold securities within the index they track. Index funds can be bought at the end of the trading day.
Exchange-Traded Funds (ETFs): ETFs are similar to index funds in that they track an underlying index's performance. However, they are structured as tradable securities and are bought and sold on stock exchanges throughout the trading day.
Like index funds, most ETFs follow a passive investment strategy. However, there are also actively managed ETFs that aim to outperform their benchmark indexes. ETFs, due to their structure, can have higher liquidity because of their intraday trading possibilities. Their prices fluctuate like individual stocks. These trading costs can bring up your expenses, making them occasionally more expensive than index funds - but not often. Some index funds might have minimum investment requirements, while ETFs generally do not. Which One Should I Choose? In general, most retail investors looking for a safe, long-term bet will choose index mutual funds over ETFs. Institutional investors typically prefer ETFs, as the expense comparisons are less meaningful for larger funds. ETFs may offer greater tax efficiency due to their unique structure, allowing for more tax-efficient trading strategies. Both index funds and ETFs provide diversified exposure to a basket of securities, typically at a low cost. Choosing between the two often depends on an investor's preferences regarding trading flexibility, expense ratios, investment minimums, and tax considerations. They’re both valuable tools for clients looking for diversity and long-term security. When I advise clients to invest in these kinds of funds, I feel good in knowing that I’m helping them reach their long-term goals while also pursuing active strategies that we’ve explored together.