Bank One Routing Number: Chase Merger Guide

What is the Bank One routing number?

Bank One Corporation used routing number 071000013 for its Illinois-based accounts, with additional routing numbers across its Midwest and Southwest footprint. Bank One was the sixth-largest bank in the United States at the time of its merger with JPMorgan Chase.

JPMorgan Chase acquired Bank One Corporation in July 2004 in a $58 billion deal. The merger brought together JPMorgan Chase's East Coast investment banking strength with Bank One's Midwest retail banking network, creating one of the most powerful financial institutions in the world.

Chase merger and account conversion

JPMorgan Chase completed the integration of Bank One accounts by 2006. All Bank One branches were rebranded as Chase, and customer accounts were migrated to Chase banking systems. The legacy Bank One routing numbers were replaced with Chase routing numbers.

Since the conversion was completed over 20 years ago, the Bank One routing number 071000013 has long been replaced. Chase uses state-specific routing numbers, and all former Bank One customers now operate under Chase routing numbers.

How to find your Chase routing number

Log into chase.com or the Chase Mobile app to view your current routing number. Chase provides routing numbers in the account details section and offers a routing number lookup tool on its website.

Common Chase routing numbers include 071000013 (which Chase retained for Illinois), 021000021 (New York), and 322271627 (California). Your specific routing number depends on the state where your account was established.

Bank One's legacy in American banking

Bank One's history dates back to City National Bank, founded in Columbus, Ohio, in 1868. Under the leadership of John B. McCoy and later Jamie Dimon (who became CEO in 2000), Bank One grew into a nationwide banking powerhouse through aggressive acquisitions.

Jamie Dimon's leadership of Bank One caught the attention of JPMorgan Chase, and the merger effectively brought Dimon to JPMorgan Chase, where he became CEO in 2005. Dimon has led JPMorgan Chase ever since, shaping it into the largest bank in the United States.

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