Once I retire, will my 401k belong to me or if it will still be managed by my previous employer?

After you retire, the money in your 401(k) is yours, subject to being fully vested, and your employer may still manage it unless you choose to move it.

Employers often set up vesting schedules, meaning you must meet certain requirements to keep employer contributions fully, particularly if you leave before being fully vested.

Many retirees opt to leave their 401(k) with their employer's chosen plan provider. However, you're not obligated to do so.

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