Telephone numbers in Singapore digits. Five digits were introduced in 1960s, whereas 5-digit and 6-digit phone numbers were introduced in 1960s as fixed lines grew, but in that year, these changed to seven digits as the introduction of new towns arose (Tampines, Jurong East, Bukit Batok, Yishun and Hougang) and a large number of new numbers were required. Rationalisation was based on geographical locale over the 12 years. In 1995, the digit '9' was added to the front of mobiland pager numbers, making numbers eight digits, and on 1 March 2002, the digit '6' was added to the front of existing fixed line telephone
Telephone numbers in China same number over time is somewhat associated with stability and reliability of the owner. As the fourth digit was introduced later, thus it is 0 for all old numbers. In further extensions, non-139,138,130 numbers were introduced. The fifth to seventh digit sometimes relates to age and location. Even earlier, before GSM, mobile phones had numbers starting with 9. Those numbers were eventually translated into 1390xx9…, where xx were local identifiers. Mobile service providers can be identified by the first three or four digits as follows: 1 - Formerly China Unicom 2 - Assigned to VNOs 3 - Operated by China