Area Code +31-23-(4400000...4400999) located in Haarlem, Noord-Holland (NH), more detail is as below. Place International Dialing Code : 31 International Prefix : 00 National Prefix : 0 National Destination Code : 23 Subscriber Number From : 4400000 Subscriber Number To : 4400999 National Destination Code Length : 2 Uses National Destination Code : Yes National Significant Number Length : 9 Number Type : G (Geographic Land Line, Fixed Line) Carrier Name : InterConnect Services B.V. Click here to buy Netherlands Area Code Database Other Information Language Code : nl (Dutch) Country Number : 528 (Netherlands) Country Code : NL (Netherlands) Region Code : NH Region Name : Noord-Holland City : Haarlem Timezone : Europe/Amsterdam Coordinated Universal Time : +01:00 Daylight Saving Time : Yes National Significant Number Minimum Length : 9 Latitude : 52.3800 Longitude : 4.6400 ‹ previous : +31-23-(4100000...4100999) next › : +31-23-(5100000...5109999) Dialling Instructions For trunk calls: 0 23 4400000 (Trunk Code + National Destination Code + Subscriber Number) For international calls: 00 31 23 4400000 (International Prefix + International Dailing Code +National Destination Code + Subscriber Number) Telephone Number List 4400000 ~ 4400999 (Count: 1,000) Example: +31-23-4400000 / 0031-23-4400000 (023-4400000 / 0-23-4400000) +31-23-4400001 / 0031-23-4400001 (023-4400001 / 0-23-4400001) +31-23-4400002 / 0031-23-4400002 (023-4400002 / 0-23-4400002) +31-23-4400003 / 0031-23-4400003 (023-4400003 / 0-23-4400003) +31-23-4400004 / 0031-23-4400004 (023-4400004 / 0-23-4400004) ...+31-23-xxxxxxx / 0031-23-xxxxxxx (023-xxxxxxx / 0-23-xxxxxxx) ...+31-23-4400995 / 0031-23-4400995 (023-4400995 / 0-23-4400995) +31-23-4400996 / 0031-23-4400996 (023-4400996 / 0-23-4400996) +31-23-4400997 / 0031-23-4400997 (023-4400997 / 0-23-4400997) +31-23-4400998 / 0031-23-4400998 (023-4400998 / 0-23-4400998) +31-23-4400999 / 0031-23-4400999 (023-4400999 / 0-23-4400999)