A non-US citizen lived and worked in the US and participated in her company's 401(k) Plan. She has since moved back to her home country, but left a small 401(k) balance behind. I would think that she can avoid paying US tax (and early withdrawal penalty) by rolling the funds into an IRA and keeping the money there, at least until she turns 59 1/2. I'm looking for some IRS guidance, but didn't see anything about non-citizens after skimming through Pub 590. Can someone point me in the right direction?