Interactive Brokers is based in the United States and also operates in several other jurisdictions. IB is required under various laws to both withhold, remit and report on income to various tax authorities, both in the U.S. and in other countries.
It is very important when operating your account to provide information concerning your primary tax residency. Rules defining this vary from nation to nation, however, since Interactive Brokers is based in the U.S. our applications use the U.S. definition of tax resident.
Determining your Tax Residency
Your tax residency determines where IB must report tax information and when tax withholding applies the rate of withholding.