Loans. Retirement account participants are generally allowed to take a 401(k) loan of up to 50 percent of the vested account balance or $50,000, whichever is less. While a 401(k) loan won't help you to build a nest egg any faster, you will probably be better off than if you simply withdrew the money, paid the taxes, and, if under age 59½, the early withdrawal penalty on the money. The balance of the loan must be paid back with interest. A 2009 Government Accountability Office report found that loans paid back to the plan in regular installments are the least damaging way to tap your retirement savings early because participants who stick to the repayment schedule are able to recover most of their losses.