Understand tax requirements when hiring a foreign contractor. Our guide provides essential insights for seamless compliance with international tax laws.Yes, it is legal under US tax law. US tax law is concerned with collecting tax. Discover essential steps for safely paying international contractors. Our guide simplifies compliance, currency, payment methods, contracts, and more. APPLICATION: Please complete and submit two copies of form BCA 13.15 to apply for an Authority to Transact Business in Illinois. Hiring international contractors can be useful but comes with challenges like IRS requirements or foreign labor laws. The payment process for a nonresident takes about 5 business days. Every bank account must be established in the name of the Board of Trustees of the University of Illinois.