<prompt> Human: Any suggestions on who to open the account with? My 401k is through Fidelity so that was my first choice for consistency but am open to others if they are better.  <response>: Fidelity is a fine choice. Vanguard and Schwab are two of the other low cost index funds leaders.Just so you can get a sense of the cost differences between them, udequeued did an analysis of the 3 Fund Portfolio of several different providers. You can see that here 