conversation: User (bagofsnakes): "So I quit my prior job in June 2013. Didn't roll over my 401k because it was performng so well. Over the past couple of months now the gains settled down and in looking to roll it over and as I was mulling around in the website I noticed something odd. There was a contribution, not an interest gain, to my account 10 months after I quit. I'd hardly expect a for profit greedy corporation like this one to continue contributing after emplotment. Anyone know of a reason why this could happen? I'd rather not call them, if it is a mistake I'm afraid they'll take it back. It was an addition of 7.8 percent of the total balance at the time."
  Self: "It was one lump sum deposit? I would guess it's probably an annual safe harbor contribution (plus possibly an additional discretionary contribution on top). They make the contribution 1x per year, so for employees who left during the plan year, the contribution can come many months after they have left the company. It would be a percentage of your total compensation during the plan year, which could really be any 12-month period of time, not necessarily in line with the calendar. (In fact because of certain reporting deadlines, many employer retirement plan years run from Oct 1-Sept 30.) And then they have up until the last day of the following plan year to make the contribution. \n\nSo if your plan made a safe harbor contribution for you in April 2015, it's theoretically possible that the plan year runs from May 1-Apr 30, and this payment was actually for the plan year ending April 30, 2013, and you'll receive an additional payment for the period you worked in May-June 2013 next April. \n\nYou may as well call and inquire; it's likely a legitimate contribution, and even if it is a mistake, they'll likely figure it out anyway during a routine audit of the plan. "
  User (bagofsnakes): "Yes, it's was just a lump sum.  No contributions since I left. I was fully vested by the time I left, if it matters. Thanks for the insight, very appreciated. "
  