John Birrer

Chief of Staff at Afiniti

Prior to joining Afiniti, John led sales and service at Charter Communications. In under two years, John led Charter to a 100% improvement in Net Promoter Score, reduced churn by more than 40 basis points, and drove improvements in Charter’s results in the Forrester Research Customer Index, all while dramatically increasing sales.

John was Senior Vice President of Customer Loyalty and Customer Service with T-Mobile USA. As part of the leadership team, he led T-Mobile to an unprecedented highest ranking in ten J.D Power & Associates Wireless Customer Care Performance Studies. His 25 years experience include 7 years on IBM’s World Wide Call Center Operations team, and 7 years with MCI Telecommunications.


Previous companies

T-Mobile logo
IBM logo
Charter Communications logo

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  • Chief of Staff

    Current role

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