China • NPA 21
☎️ Central Office Exchange (NXX)
+86 (21) 663 Exchange Code
Technical registry directory for telephone subscriber numbers starting with +86 (21) 663. Central office block assigned to Shanghai, China.
Standard Subscriber Format
+86 (21) 663-XXXX
Telecom Carrier
Local Network Carrier
Area Code (NPA)
21
Primary Location
Shanghai
Service Type
Landline
📋 Central Office Exchange 663 Routing Details
The 663 exchange code (central office prefix) operates within the 21 Numbering Plan Area (NPA) servicing Shanghai, China. All assigned subscriber lines in this block follow ITU-T E.164 national routing protocols.
Telecommunication services within the +86 (21) 663 prefix range are primarily provisioned by Local Network Carrier, delivering local landline voice lines and network routing.
🌐 Dialing Instructions
-
•
Domestic Calls: Dial
021 663-1234or local national format. -
•
International Calls: Dial
+86 21 663-1234from outside China. -
•
E.164 Standard:
+8621663XXXX
📞 Nearby Exchanges in Area Code 21
View All Area Code 21 Exchanges ›❓ Frequently Asked Questions
What area code is +86 (21) 663?
Phone numbers starting with +86 (21) 663 belong to the 21 area code in Shanghai, China, routed via exchange block 663.
How do I call a 663 exchange number from abroad?
To call this prefix internationally, dial your local exit code (e.g., 011 in North America or + globally), followed by +86, then 21, and the subscriber number.
Which provider operates the 663 prefix in Shanghai?
Telecom services for the 663 exchange block in Shanghai are primarily assigned to Local Network Carrier for Landline connections.