The Senate's Permanent Subcommittee on Investigations said the companies used places such as the Cayman Islands so they did not have to pay US taxes.
The chairman of the panel said their practices ranged from "egregious to dubious validity".
Carl Levin has been investigating offshore tax havens for years.
He said the industry was probably the number one user of these offshore entities to transfer intellectual property.
The committee said that between 2009 and 2011, Microsoft moved $21bn (£13bn) offshore, almost half its US retail sales revenue.
The panel said the moved saved it up to $4.5bn in taxes on goods sold within the US.
It also said the company moves royalty revenue to divisions in lower-tax nations, including Singapore and the Republic of Ireland.
The panel said Hewlett-Packard funded US operations with inter-company loans, using an exception in the law for short-term loans, to avoid billions of dollars in taxes.