Conexus, Cornerstone, and Synergy Credit Unions are exploring a merger to create a resilient credit union. Learn more here.

Report a Lost or Stolen Card

Member Card® Debit Card


To report a lost or stolen Member Card® debit card, please call: 1.855.875.2255 during business hours. 


Outside regular credit union hours please call:
Toll free within North America: 1.888.277.1043

Outside North America: 1.905.305.4099 

Cornerstone Collabria Mastercard® 


Cardholder support team members work on your behalf 24/7 every day of the year.

To report a lost or stolen Cornerstone Collabria Mastercard®, please call: 1.855.341.4643

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