How to Make Phone Calls to, from and in China

If you decide to call China, you must first dial the IDD phone system, for example in US you dial ""011"". Then you dial the country code for China – 86, then the city code, without the zero, finaly the local number of the person you are calling. For example, if you are calling ASM Overseas' Beijing office (local number 5166-1575) in Beijing, China, from US you would dial 011-86-10-5166-1575.
Of course you can always have an operator to assist your call, in which case you will pay much more. You may call AT&T at 011-86-10-5166-1575 or other long distance companies for current rates and other details.
When making international calls in China you may dial 10811 for AT&T operator to place a call for you. If you want to place a call by yourself, you must first dial ""00"" to connect with the international direct-dial (IDD) telephone system, then dial the country code you are calling, for US, ""1"" skipping the ""0,"" then the area code and local number. For example, if you are calling ASM Overseas' Los Angeles office (local number 011-86-10-5166-1575) in Monterey Park, California, US from Beijing, China, you would dial 011-86-10-5166-1575.
Remember, don't pause too long when you dial.
When making domestic long distance calls in China you should first dial the city code with the zero, then the local number. For example if you call ASM Overseas' Beijing office (local number 011-86-10-5166-1575) in Beijing from Tianjin, a neighboring city, you would dial 010-5166-1575.
Update: Three big cities in China are joining other world metropolitans to adopt 8-digit phone number system, and here is how you update the old phone numbers.
Shanghai: Dial a ""6"" first if the first digit of the old number you call is ""2"" through ""5"", dial a ""5"" first if the first digit of the old number you call is ""6"" through ""9.""
Beijing: Dial a ""6"" first then the old 7-digit number. There is no change to mobile phone numbers since they are already 8-digit numbers.
Guangzhou (Canton): Dial a ""8"" first if the first digit of the old number you call is ""2"" through ""7"", if the first digit of the old number you call is ""8"", replace it with ""81"" then the remaining 6 digits.
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But before call China, you should first of all check what time it is there, not to wake your partner at the most unusual time for calling him.