Post-tax 401K is better than pre-tax only if The person decides to immediately convert to Roth IRA (since in Roth earnings will be tax-free while in post-tax, they are tax-deferred, this depends on whether the employee permits it or not. Do note that stocks held in a taxable account will be taxed at a lower rate than in tax-deferred account where they are taxed as normal income upon retirement. Invest in three things Total US stock market (VTI or VTSAX) Total world stock market excluding US (VEU or VXUS or VFWIX) Total bond market (BND) ~ %age allocation should be almost the person’s age (conservative rule - reduce this %age to be more aggressive) Split between (1) and (2) should be roughly 80:20 or 70:30.