Area Code +81-503-(5370000...5379999) 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 : 5370000 Subscriber Number To : 5379999 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-(5360000...5369999) next › : +81-503-(5380000...5389999) Dialling Instructions For trunk calls: 0 503 5370000 (Trunk Code + National Destination Code + Subscriber Number) For international calls: 010 81 503 5370000 (International Prefix + International Dailing Code +National Destination Code + Subscriber Number) Telephone Number List 5370000 ~ 5379999 (Count: 10,000) Example: +81-503-5370000 / 01081-503-5370000 (0503-5370000 / 0-503-5370000) +81-503-5370001 / 01081-503-5370001 (0503-5370001 / 0-503-5370001) +81-503-5370002 / 01081-503-5370002 (0503-5370002 / 0-503-5370002) +81-503-5370003 / 01081-503-5370003 (0503-5370003 / 0-503-5370003) +81-503-5370004 / 01081-503-5370004 (0503-5370004 / 0-503-5370004) ...+81-503-xxxxxxx / 01081-503-xxxxxxx (0503-xxxxxxx / 0-503-xxxxxxx) ...+81-503-5379995 / 01081-503-5379995 (0503-5379995 / 0-503-5379995) +81-503-5379996 / 01081-503-5379996 (0503-5379996 / 0-503-5379996) +81-503-5379997 / 01081-503-5379997 (0503-5379997 / 0-503-5379997) +81-503-5379998 / 01081-503-5379998 (0503-5379998 / 0-503-5379998) +81-503-5379999 / 01081-503-5379999 (0503-5379999 / 0-503-5379999)