The panel has conducted a bipartisan survey over the past year into the market dominance of tech giants and its effects on consumers.
This is the first congressional journal of its kind on the technology industry. It aimed to determine whether existing competition policies and century-old antitrust laws are adequate or whether new legislation and additional funding are needed.
The four CEOs are expected to testify from a distance.
The hearing was originally scheduled for Monday. It has been postponed to allow lawmakers on the committee to participate in commemorations at the United States Capitol Monday and Tuesday for Representative John Lewis, the civil rights icon and longtime congressman from Georgia who died on July 17. .