Service codes, commonly called N11 codes because of their format, are used to provide three-digit dialing access special services.

In the U.S., the FCC administers N11 codes, and recognizes only 211, 311, 511, and 711 as nationally assigned. Other codes have traditional uses as shown in the table below.

X11 CODE            DESCRIPTION 

211            Community Information and Referral Services (US)   

311       Non-Emergency Police and Other Governmental Services (US)   

411       Local Directory Assistance       

511       Traffic and Transportation Information (US); Reserved (Canada)          

611       Repair Service 

711            Telecommunications Relay Service (TRS)   

811            Business Office

911            Emergency