WASHINGTON—Apple Inc. Chief Executive Tim Cook defended the technology giant's tax practices in front of Senate investigators on Tuesday, arguing the company pays all taxes due and that its use of foreign subsidiaries doesn't affect its U.S. tax bill.

Mr. Cook's appearance on Capitol Hill followed the disclosure his company has paid no corporate income taxes on tens of billions of dollars in overseas income during the past four years, according to a report from the U.S. Senate's Permanent Subcommittee on Investigations released...