Here's a common retiree question...Does my 401k or 403b employer plan offer an income annuity when i retire?  

Most plans do not offer any type of income annuity.   Some plans will allow you to set up a systematic withdrawal plan (SWP) to provide regular monthly income.  A surprising number of plans however are "full payout" plans,  they simply don't allow partial or sytematic withdrawals at retirement.   

You'll want to consider an IRA rollover  if you're plan is restrictive...Most IRA accounts are very flexible and will allow partial, systematic and even allow you to put a portion in an annuity. 

If you are close to retirement..call your employer plan's toll free number and inquire about the withdrawal options.