or if your spouse has self employment income she could establish a solo 401k at Vanguard and then move the funds from the old 401k to the solo 401k via a trustee to trustee transfer. This may be the ideal route if your income is above the limits for deductible tIRA and direct Roth IRA contributions, in which case you want to do a backdoor Roth IRA, but you don't want the conversion to be subject to pro rata taxation. If your spouse doesn't anticipate doing backdoor Roth IRAs in the future then just rollover the old 401k to an IRA at Vanguard. The decision on whether to convert pretax dollars to Roth or not primarily depends on your current marginal tax rate