The campaign comes as several US states have passed or are considering stricter new abortion laws.
They include controversial “heartbeat bills” which would ban abortion once a foetal heartbeat is detectable.
The letter published in the New York Times said curbs on abortion threaten the health of staff and customers.
The chief executives of Slack, Square, Zoom, and Bloomberg were among those who signed the letter entitled “Don’t Ban Equality”, according to the American Civil Liberties Unionwhich helped organise the campaign.
“Restricting access to comprehensive reproductive care, including abortion, threatens the health, independence and economic stability of our employees and customers,” it said.
“It impairs our ability to build diverse and inclusive workforce pipelines, recruit top talent across the states, and protect the wellbeing of all the people who keep our businesses thriving day in and out.”
“Simply put, it goes against our values and is bad for business,” the letter said.
The heartbeat bills seek to make abortion illegal as soon as a foetus’ heartbeat is detectable.
In most cases, this is at the six-week mark of a pregnancy – before many women even know they are pregnant.
A number of US media giants have publicly statedthey will reconsider filming in Georgiaif the state’s strict new abortion law takes effect.
Disney, Netflix and WarnerMedia have all objected to the legislation.
Bob Iger, the chief executive of Disney, said Georgia’s heartbeat bill would make it “difficult” to keep filming there.
WarnerMedia said it would reconsider Georgia “if the new law holds” and Netflix has said it would “rethink” its productions in the state should the law take effect.
Georgia makes billions of dollars from film and television productions.