Within the last year I've stopped contributing to my Betterment Roth IRA and have instead elected to put all my retirement savings into the ROTH TSP. Is this a good plan? Especially given how advanced I'm hearing that companies like Betterment are?
Do you get TSP matching? If so, *always* contribute enough to maximize the match. Betterment is unlikely to double your money the day you put it in. For unmatched funds, TSP is probably still slightly better since their ER is lower, and the primary selling point of Betterment (tax loss harvesting) is moot inside of a Roth.
However, your goal should be to contribute the legal maximum to
both accounts, since the contribution limits are separate ($18K TSP, $5500 IRA). I'm planning to do so this year (first time ever, first full year since finding MMM; no coincidence).