• Chongqing was part of Sichuan and it had the 811 city code until 8 March 1997. In April 1997, Chongqing became the fourth municipality under the direct jurisdiction of the central government.
• All counties in Chongqing with old 811 code now has the new 23 code.
• Chongqin local phone number was changed to 8 digits on March 8, 1997. The rules are xxx-xxxx to 6xxx-xxxx for regular numbers, and xxx-xxxx to x8xx-xxxx for mobile phone numbers.

ÖØÇì	23	Chongqing
±±íÕ	23	Beipei (was 8215, then 811)