In every US state, federal income tax is payable on top of state taxes. Federal tax cannot be avoided and applies in every state, even where a state’s own tax is low or non-existent. If you are applying for an investor visa to the USA, your company should, in the years ahead, generate profits exceeding what you and your family need to live on.

The USA has a high tax-free allowance (more than USD 10,000 per person), and married couples may file a joint return, effectively doubling it (to more than USD 20,000). Progressive rates then apply. The first approx. USD 10,000 of income/profit above the allowance (approx. USD 20,000 for married couples) is taxed at just 10%. The next approx. USD 30,000 (approx. USD 60,000 for married couples) is taxed at only 12%. This is followed by a band of approx. USD 35,000 (approx. USD 70,000 for married couples) taxed at only 22%.
For example, on a profit of USD 60,000, a married couple’s effective federal tax rate will be 5-10%. So, if your business plans allow, I would aim for the highest possible profit and turnover.

You hold an E2 investor visa, live in the USA and have income from a country other than the USA

Suppose you hold an E2 visa, live in the USA and earn rental income or proceeds from property sales in a high-tax country that has a double taxation treaty with the USA, e.g. Slovakia. In that case, you will probably pay tax on this type of income only in Slovakia.

As for profits made by your companies in other high-tax countries that have a double taxation treaty with the USA, such as a company in Slovakia, Slovak companies will in this case pay tax only in Slovakia, although there may be several exceptions to this rule as well.

If you have an offshore company that pays no tax at all, that income may well give rise to an obligation to pay tax in the USA.