What is your mailing address/phone number? 3Rivers PO Box 2573 Fort Wayne, IN 46801-2573 260.490.8328 800.825.3641 You can also contact us online. Have more questions? Submit a request 0 Comments Article is closed for comments. Related articles What are your branch locations and hours? What is 3Rivers routing number? What kind of account do I need to open for my independent consultant business (e.g. Mary Kay, Pampered Chef)?