ISDN is very popular in Germany

　　In Germany, ISDN is very popular with an installed base of 25 million channels (29% of all subscriber lines in Germany as of 2003 and 20% of all ISDN channels worldwide). Due to the success of ISDN, the number of installed analog lines is decreasing. Deutsche Telekom (DTAG) offers both BRI and PRI. Competing phone companies often offer ISDN only and no analog lines.

　　However, these operators generally offer free hardware that also allows the use of POTS equipment, such as NTBAs[clarification needed] with integrated terminal adapters. Because of the widespread availability of ADSL services, ISDN is today primarily used for voice and fax traffic, but is still very popular thanks to the pricing policy of German telecommunication providers.

　　Today ISDN (BRI) and ADSL/VDSL are often bundled on the same line, mainly because the combination of ADSL with an analog line has no cost advantage over a combined ISDN-ADSL line. Some German operators started to implement Next Generation Networking, generally realized via DSL and unbundled local loop. However, a few operators offer the same services via the cable television infrastructure or, in selected areas, via FTTH. Because of the popularity of ISDN, virtually all these telecommunication providers bundle their products with residential gateways that include both integrated analog telephony adapters and ISDN-NGN adapters.

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