<prompt> Human: Is it generally better to have an index fund like SWTSX or a target fund like SWORX as your sole investment in a Roth IRA?  <response>: Remember that either of those options contains hundreds, if not thousands, of individual stocks and provides broad exposure to the U.S. stock market. The difference is that a target date fund would also include exposure to international stocks non-US companies; a case can be made that US companies provide plenty of international exposure and bonds. That last part might be the most important consideration: the target date fund provides some and increasing over time exposure to bonds, which makes it diversified in ways that an index fund is not. This is particularly important later on, as retirement looms within 20 years. The other thing to consider are expenses: some target date funds contain only index funds, others have actively managed funds. The expenses on SWORX are too high for my taste 0.79. If I were you, Id compare the index fund to a Schwab Target Date Index fund In sum, Id go with a Schwab Target Date Index fund, which contains everything in the other option but is more diversified by type e.g., international stocks, bonds. 