Area Code +81-503-(6380000...6389999) 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 : 6380000 Subscriber Number To : 6389999 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-(6370000...6379999) next › : +81-503-(6390000...6399999) Dialling Instructions For trunk calls: 0 503 6380000 (Trunk Code + National Destination Code + Subscriber Number) For international calls: 010 81 503 6380000 (International Prefix + International Dailing Code +National Destination Code + Subscriber Number) Telephone Number List 6380000 ~ 6389999 (Count: 10,000) Example: +81-503-6380000 / 01081-503-6380000 (0503-6380000 / 0-503-6380000) +81-503-6380001 / 01081-503-6380001 (0503-6380001 / 0-503-6380001) +81-503-6380002 / 01081-503-6380002 (0503-6380002 / 0-503-6380002) +81-503-6380003 / 01081-503-6380003 (0503-6380003 / 0-503-6380003) +81-503-6380004 / 01081-503-6380004 (0503-6380004 / 0-503-6380004) ...+81-503-xxxxxxx / 01081-503-xxxxxxx (0503-xxxxxxx / 0-503-xxxxxxx) ...+81-503-6389995 / 01081-503-6389995 (0503-6389995 / 0-503-6389995) +81-503-6389996 / 01081-503-6389996 (0503-6389996 / 0-503-6389996) +81-503-6389997 / 01081-503-6389997 (0503-6389997 / 0-503-6389997) +81-503-6389998 / 01081-503-6389998 (0503-6389998 / 0-503-6389998) +81-503-6389999 / 01081-503-6389999 (0503-6389999 / 0-503-6389999)