"E" is Eastern Time Zone, "C" is Central Time Zone, "M" is Mountain Time Zone, and "P" is Pacific Time Zone. Occasionally, an area code will fall in more than one time zone. In this case, the abbreviation is a combination of the previous abbreviations. Some area codes are shown with time zones referencing Universal Coordinated Time (UTC).
Additional technical status can be retrived from the North American Numbering Plan Administration on the 562 area code specific link here.
Area code 562 went live into service on January 25, 1997.  It was formed as a subdivision of the 310 area code.
Due to popularity, this area code is starting to run out of free telephone numbers for people to use which means that this area code is technically referred to as being "in jeoparady." Planning is underway and notices have been distributed regarding the area code subdivision.
LONG BEACH, WHITTIER, PICORIVERA, NORWALK, ALAMITOS, LAKEWOOD, LA HABRA, CMTN CMTN, DOWNEY, CMTN GRDN
Number of major cities served
Names of major cities served (ZIP code)
Long Beach (90802), Whittier (90602), Pico Rivera (90660), Norwalk (90650), Huntington Beach (92649), Huntingtn Bch (92649), Anaheim (92805), Federal (92805), Long Beach (90808), La Habra (90631), La Habra Heights (90631), La Habra Hgts (90631), La Habra Hts (90631), Long Beach (90813), Paramount (90723), Compton (90220), Crystal City (90220), Rancho Dominguez (90220), Rncho Domingz (90220), Santa Fe Springs (90670), Santa Fe Spgs (90670), Downey (90241), Gardena (90247), Signal Hill (90807), Long Beach (90807), Bixby Knolls (90807), Seal Beach (90740), Downey (90242), Artesia (90701), Cerritos (90701), Lakewood (90805), Long Beach (90805), North Long Beach (90805), Signal Hill (90804), Long Beach (90804), East Long Beach (90804), Bellflower (90706), Whittier (90606), Los Nietos (90606), Long Beach (90815), Los Angeles (90071), Arco (90071), Arco-plaza (90071), Bell (90201), Bell Gardens (90201), Cudahy (90201), Whittier (90604), Whittier (90603)
39 telephone companies servicing the 562 area code
List of telephone companies
INFOTELECOM, LLC - CA, ROYAL STREET COMMUNICATIONS, LLC, NEW CINGULAR WIRELESS PCS, LLC, MPOWER COMMUNICATIONS CORP - CA, U.S. TELEPACIFIC CORP. - CA, NEXTEL COMMUNICATIONS, INC., LEVEL 3 COMMUNICATIONS, LLC - CA, XO CALIFORNIA, INC., T-MOBILE USA, INC., SPRINT SPECTRUM L.P., AT&T LOCAL, USA MOBILITY WIRELESS, INC., MCIMETRO ACCESS TRANSMISSION SERVICES LLC, BROADWING COMMUNICATINS. LLC - CA, CELLCO PARTNERSHIP DBA VERIZON WIRELESS - CA, VERIZON CALIFORNIA INC.-CA (GTE), CHARTER FIBERLINK CA-CCO, LLC - CA, PACIFIC BELL, DIGITCOM SERVICES, INC., TW TELECOM OF CALIFORNIA LP - CA, PACIFIC BELL - CLEC, TELEPORT COMMUNICATIONS GROUP - LOS ANGELES, PAC - WEST TELECOMM, INC., COOK TELECOM, INC., COX CALIFORNIA TELCOM, INC. - CA, 360NETWORKS (USA) INC. - CA, ALLEGIANCE TELECOM, INC. - CA, PAETEC COMMUNICATIONS, INC. - CA, NETWORK SERVICES LLC, THE TELEPHONE CONNECTION OF LOS ANGELES, INC., NORTH COUNTY COMMUNICATIONS CORP. - CA, O1 COMMUNICATIONS, INC. - CA, GLOBAL CROSSING LOCAL SERVICES, INC.-CA, POINTE COMMUNICATIONS CORP. - CA, COMMPARTNERS, LLC - CA, PG TELECOM OF CALIFORNIA INC. - CA, CROWN CELLULAR & PAGING, MCI WORLDCOM COMMUNICATIONS, INC., CA, SHELCOMM