The remote video hearing will be the fourth for Facebook's Mark Zuckerberg and Twitter's Jack Dorsey since last July and the third for Google's Sundar Pichai: evidence of how the companies' vast economic and political power has landed them squarely in the crosshairs of Democrats and Republicans alike.
"Whether it be falsehoods about the Covid-19 vaccine or debunked claims of election fraud, these online platforms have allowed misinformation to spread, intensifying national crises with real-life, grim consequences for public health and safety," said the heads of the two Congressional subcommittees holding the hearing, in a statement.
A recent backlash against the tech behemoths, which dominate key economic sectors, has intensified as their influence has grown during the coronavirus pandemic.
"I don't expect more than theater" at the hearing, said analyst Carolina Milanesi of market research firm Creative Strategies.
"It's still politics and you are still going to have the whole Republicans-versus-Democrats and free speech coming into play."
US President Joe Biden this week named a prominent advocate of breaking up Big Tech firms, Lina Khan, to head the Federal Trade Commission, in a move suggesting an aggressive posture on antitrust enforcement.