Area Code +81-503-(3790000...3799999) located in VoIP, more detail is as below. Place International Dialing Code : 81 International Prefix : 010 National Prefix : 0 National Destination Code : 503 Subscriber Number From : 3790000 Subscriber Number To : 3799999 National Destination Code Length : 3 Uses National Destination Code : Yes National Significant Number Length : 10 Number Type : V (VoIP, Location Independent fixed land line) Carrier Name : NTT Communications Click here to buy Japan Area Code Database Other Information Language Code : ja (Japanese) Country Number : 392 (Japan) Country Code : JP (Japan) City : VoIP Timezone : Asia/Tokyo Coordinated Universal Time : +09:00 Daylight Saving Time : No National Significant Number Minimum Length : 10 Latitude : None Longitude : None ‹ previous : +81-503-(3780000...3789999) next › : +81-503-(3800000...3809999) Dialling Instructions For trunk calls: 0 503 3790000 (Trunk Code + National Destination Code + Subscriber Number) For international calls: 010 81 503 3790000 (International Prefix + International Dailing Code +National Destination Code + Subscriber Number) Telephone Number List 3790000 ~ 3799999 (Count: 10,000) Example: +81-503-3790000 / 01081-503-3790000 (0503-3790000 / 0-503-3790000) +81-503-3790001 / 01081-503-3790001 (0503-3790001 / 0-503-3790001) +81-503-3790002 / 01081-503-3790002 (0503-3790002 / 0-503-3790002) +81-503-3790003 / 01081-503-3790003 (0503-3790003 / 0-503-3790003) +81-503-3790004 / 01081-503-3790004 (0503-3790004 / 0-503-3790004) ...+81-503-xxxxxxx / 01081-503-xxxxxxx (0503-xxxxxxx / 0-503-xxxxxxx) ...+81-503-3799995 / 01081-503-3799995 (0503-3799995 / 0-503-3799995) +81-503-3799996 / 01081-503-3799996 (0503-3799996 / 0-503-3799996) +81-503-3799997 / 01081-503-3799997 (0503-3799997 / 0-503-3799997) +81-503-3799998 / 01081-503-3799998 (0503-3799998 / 0-503-3799998) +81-503-3799999 / 01081-503-3799999 (0503-3799999 / 0-503-3799999)