Police said Williams walked into the Fort Bragg Federal Credit Union on Raeford Road shortly after 11 a.m. and handed a teller a note demanding cash.
After getting money, she left in a dark-colored SUV.
Detectives believe Williams may be travelling with a 39-year-old black male who is 5 '8" and weighs 170 pounds.
Williams has been charged with robbery with a dangerous weapon.
Anyone with information about Williams is urged to contact detectives with the Fayetteville Police Department at (910) 433-1851 ext. 2903 or call CrimeStoppers at (910) 483-TIPS (8477).