The suspect, identified Tuesday as 26-year-old Kip Lessard, was arrested Monday at his home in Chandler, according to a release from the FBI.
Initially, agents said he was connected to 10 robberies, though the FBI said he would be charged with 16 robberies.
Investigators said Lessard targeted banks, grocery stores and fast-food restaurants in a variety of cities, including Scottsdale, Chandler, Glendale and Surprise, among others between August 4 and October 11.
Authorities say in each of the robberies, he would pretend to be a customer by ordering food or picking up store items.
Once at the counter, Lessard would reportedly supply the employee with a note informing them of the robbery or would show a handgun and demand money.
The FBI said Lessard had been transferred to the custody of the U.S. Marshals.