Area Code +1-301-(3129000...3129999) located in Bethesda, Maryland (MD), more detail is as below. Place International Dialing Code : 1 International Prefix : 011 National Prefix : 1 National Destination Code : 301 Subscriber Number From : 3129000 Subscriber Number To : 3129999 National Destination Code Length : 3 Uses National Destination Code : Yes National Significant Number Length : 10 Number Type : M (Mobile, Cellular) Carrier Name : NEW CINGULAR WRLS DC Click here to buy United States Area Code Database Other Information Language Code : en (English) Country Number : 840 (United States) Country Code : US (United States) Region Code : MD Region Name : Maryland City : Bethesda Timezone : America/New_York Coordinated Universal Time : -05:00 Daylight Saving Time : Yes National Significant Number Minimum Length : 10 Latitude : 38.9800 Longitude : -77.1100 ‹ previous : +1-301-(3128000...3128999) next › : +1-301-(3130000...3130999) Dialling Instructions For trunk calls: 0 301 3129000 (Trunk Code + National Destination Code + Subscriber Number) For international calls: 011 1 301 3129000 (International Prefix + International Dailing Code +National Destination Code + Subscriber Number) Telephone Number List 3129000 ~ 3129999 (Count: 1,000) Example: +1-301-3129000 / 0111-301-3129000 (1301-3129000 / 1-301-3129000) +1-301-3129001 / 0111-301-3129001 (1301-3129001 / 1-301-3129001) +1-301-3129002 / 0111-301-3129002 (1301-3129002 / 1-301-3129002) +1-301-3129003 / 0111-301-3129003 (1301-3129003 / 1-301-3129003) +1-301-3129004 / 0111-301-3129004 (1301-3129004 / 1-301-3129004) ...+1-301-xxxxxxx / 0111-301-xxxxxxx (1301-xxxxxxx / 1-301-xxxxxxx) ...+1-301-3129995 / 0111-301-3129995 (1301-3129995 / 1-301-3129995) +1-301-3129996 / 0111-301-3129996 (1301-3129996 / 1-301-3129996) +1-301-3129997 / 0111-301-3129997 (1301-3129997 / 1-301-3129997) +1-301-3129998 / 0111-301-3129998 (1301-3129998 / 1-301-3129998) +1-301-3129999 / 0111-301-3129999 (1301-3129999 / 1-301-3129999)