I assumed we were talking about money for a home down payment, which would not normally go into a 401k. Getting it out would require a 401k loan, and a 401k loan for a six-figure amount is almost always a terrible idea. The only other way to get it out would be to take an unqualified distribution and get hit with a significant fine.

Most 401k loans become due in full if you leave your job. That traps you in your job until you pay it back, because if you had enough cash to pay the loan outright, you would not have needed the loan in the first place. Unless you have an unusually good severance agreement with your employer that would enable you to pay back the loan if you leave your job or get fired, taking out a 401k loan is a bad idea.