<prompt> Human: Should I just roll it it into my IRA or should I try to see if I can roll it into my new 401k at the new job?Its in Vanguard now, as is my IRA and sons 529. New place uses Fidelity.Assistant: Normally the best thing to do is to roll it into an IRA. An IRA at a good company like Vanguard will give you access to all the funds and investments you could get in a 401k, but also way more than just that. Theres just much more freedom in an IRA than a 401k, where you are stuck with whatever investments are offered to the group. And hey, if you really like the 401k investment options at your new company whats stopping you from mimicking those choices in your IRA?Human: How does that whole compounding interest thing work?With 86k in this account would it be better to keep it going over starting a new one? In the new company Ill take the match, because free money, but will it grow like the old one because it will start at 0?Assistant: The math works out the same for compound interest whether the money is in one account or two.Human: Then Ill just roll it into my existing IRA, do one of those bank transfer things so I wont get hurt. This was the main reason I wanted to see what I could do, since the math all works out I will just do what I can with this and then start new at the new guy.  <response>: Make sure that you use the rollover mechanism. If you just withdraw the money from one and put it into the other you will get nailed with taxes 