Area Code +81-503-(6390000...6399999) 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 : 6390000 Subscriber Number To : 6399999 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-(6380000...6389999) next › : +81-503-(6400000...6409999) Dialling Instructions For trunk calls: 0 503 6390000 (Trunk Code + National Destination Code + Subscriber Number) For international calls: 010 81 503 6390000 (International Prefix + International Dailing Code +National Destination Code + Subscriber Number) Telephone Number List 6390000 ~ 6399999 (Count: 10,000) Example: +81-503-6390000 / 01081-503-6390000 (0503-6390000 / 0-503-6390000) +81-503-6390001 / 01081-503-6390001 (0503-6390001 / 0-503-6390001) +81-503-6390002 / 01081-503-6390002 (0503-6390002 / 0-503-6390002) +81-503-6390003 / 01081-503-6390003 (0503-6390003 / 0-503-6390003) +81-503-6390004 / 01081-503-6390004 (0503-6390004 / 0-503-6390004) ...+81-503-xxxxxxx / 01081-503-xxxxxxx (0503-xxxxxxx / 0-503-xxxxxxx) ...+81-503-6399995 / 01081-503-6399995 (0503-6399995 / 0-503-6399995) +81-503-6399996 / 01081-503-6399996 (0503-6399996 / 0-503-6399996) +81-503-6399997 / 01081-503-6399997 (0503-6399997 / 0-503-6399997) +81-503-6399998 / 01081-503-6399998 (0503-6399998 / 0-503-6399998) +81-503-6399999 / 01081-503-6399999 (0503-6399999 / 0-503-6399999)