Area Code +81-503-(3730000...3739999) 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 : 3730000 Subscriber Number To : 3739999 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-(3720000...3729999) next › : +81-503-(3740000...3749999) Dialling Instructions For trunk calls: 0 503 3730000 (Trunk Code + National Destination Code + Subscriber Number) For international calls: 010 81 503 3730000 (International Prefix + International Dailing Code +National Destination Code + Subscriber Number) Telephone Number List 3730000 ~ 3739999 (Count: 10,000) Example: +81-503-3730000 / 01081-503-3730000 (0503-3730000 / 0-503-3730000) +81-503-3730001 / 01081-503-3730001 (0503-3730001 / 0-503-3730001) +81-503-3730002 / 01081-503-3730002 (0503-3730002 / 0-503-3730002) +81-503-3730003 / 01081-503-3730003 (0503-3730003 / 0-503-3730003) +81-503-3730004 / 01081-503-3730004 (0503-3730004 / 0-503-3730004) ...+81-503-xxxxxxx / 01081-503-xxxxxxx (0503-xxxxxxx / 0-503-xxxxxxx) ...+81-503-3739995 / 01081-503-3739995 (0503-3739995 / 0-503-3739995) +81-503-3739996 / 01081-503-3739996 (0503-3739996 / 0-503-3739996) +81-503-3739997 / 01081-503-3739997 (0503-3739997 / 0-503-3739997) +81-503-3739998 / 01081-503-3739998 (0503-3739998 / 0-503-3739998) +81-503-3739999 / 01081-503-3739999 (0503-3739999 / 0-503-3739999)