Is there legal reason for restricting someone under 59-1/2 from an in-service rollover from a 401K to an IRA?
Yes, this is restricted by law.  In plain language, you can find it on the IRS website (under the heading "When Can a Retirement Plan Distribute Benefits?"): 401(k), profit-sharing, and stock bonus plans Employee elective deferrals (and earnings, except in a hardship distribution) -- the plan may permit a distribution when you: •terminate employment (by death, disability, retirement or other severance from employment); •reach age 59½; or •suffer a hardship. Employer profit-sharing or matching contributions -- the plan may permit a distribution of your vested accrued benefit when you: •terminate employment (by death, disability, retirement or other severance from employment); •reach the age specified in the plan (any age); or •suffer a hardship or experience another event specified in the plan. Form of benefit - the plan may pay benefits in a single lump-sum payment as well as offer other options, including payments over a set period of time (such as 5 or 10 years) or a purchased annuity with monthly lifetime payments.  Source: https://www.irs.gov/retirement-plans/plan-participant-employee/when-can-a-retirement-plan-distribute-benefits If you want to actually see it in the law, check out 26 USC 401(k)(2)(B)(i), which lists the circumstances under which a distribution can be made.  You can get the full text, for example, here: https://www.law.cornell.edu/uscode/text/26/401 I'm not sure what to say about the practice of the company that you mentioned in your question.  Maybe the law was different then?
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### Instruction:
Is there legal reason for restricting someone under 59-1/2 from an in-service rollover from a 401K to an IRA?

### Response:
Yes, this is restricted by law.  In plain language, you can find it on the IRS website (under the heading "When Can a Retirement Plan Distribute Benefits?"): 401(k), profit-sharing, and stock bonus plans Employee elective deferrals (and earnings, except in a hardship distribution) -- the plan may permit a distribution when you: •terminate employment (by death, disability, retirement or other severance from employment); •reach age 59½; or •suffer a hardship. Employer profit-sharing or matching contributions -- the plan may permit a distribution of your vested accrued benefit when you: •terminate employment (by death, disability, retirement or other severance from employment); •reach the age specified in the plan (any age); or •suffer a hardship or experience another event specified in the plan. Form of benefit - the plan may pay benefits in a single lump-sum payment as well as offer other options, including payments over a set period of time (such as 5 or 10 years) or a purchased annuity with monthly lifetime payments.  Source: https://www.irs.gov/retirement-plans/plan-participant-employee/when-can-a-retirement-plan-distribute-benefits If you want to actually see it in the law, check out 26 USC 401(k)(2)(B)(i), which lists the circumstances under which a distribution can be made.  You can get the full text, for example, here: https://www.law.cornell.edu/uscode/text/26/401 I'm not sure what to say about the practice of the company that you mentioned in your question.  Maybe the law was different then?