William Bainton Slater Jr.

7 July, 193312 July, 2021

William B. Slater passed away on July 12, 2021 on Cape Cod, MA, after a brief illness. He had turned 88 years old on July 7. Bill was born in Pawtucket, Rhode Island and lived in Providence and later in Saugerties, NY. His father died when he was a very young child and his mother later remarried a businessman from upstate New York. Bill was the youngest of five children and the last to die.

Bill was a graduate of Tabor Academy in Marion, MA and then Dartmouth College in Hanover, NH. Upon graduation, Bill entered the US Army and fulfilled his military obligation. He then went on to earn his MBA in finance from Columbia University in New York City. Over the next fifteen years, Bill held a number of executive finance and treasury positions in a variety of firms, including Mobil Oil, The Singer Company, Merrill Lynch, Gulf & Western and ending with the Pension Benefit Guaranty Corporation in Washington, DC. The remaining thirty years of his career were spent in Chicago as a Market Maker and later a securities trader on the Chicago Board of Options Exchange.

Bill was married and divorced in his early adult years and then was the long term life partner of Mary Kay Sullivan for 43 years, with whom he shared many great life experiences and exciting travel. Bill was the proud father of six children (Bill, Pam, Bobbie (deceased), Laura, Kitty and Holly) and grandfather of ten (two granddaughters and eight grandsons).

Bill had innumerable close friends and was highly regarded for his kindness, wonderful sense of humor and innate intelligence. He will be deeply missed by all who knew him.

In lieu of flowers, contributions may be made in Bill’s honor to Trustees of Dartmouth College, 1955 Dartmouth Class, 6066 Development Office, Hanover, New Hampshire 03755-4400. For online condolences, please visit


No public services are scheduled at this time. Receive a notification when services are updated.


William Bainton Slater Jr.

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