Almost two years ago (my how time flies), my husband and I took an amazing vacation on a cruise of the Mediterranean. When I returned from that trip, I wrote a blog about the nuances for foreign companies doing business in the United States as it relates to state tax issues. Income tax and sales tax in the US are challenging concepts not only for foreign companies, but also domestic companies. And as the state tax landscape has changed recently as a result of the recent South Dakota v. Wayfair (2018) decision, it may also be impacting foreign companies doing business here as well.So, to recap from that prior blog article, and to elaborate a bit further, here are some of the major areas for foreign companies to consider as they begin doing business in the US.The Concept of Nexus – “Nexus” is the minimum contact a company must have with a state in order for the state to be able to impose its tax laws on the company. Historically (until the Wayfair case in June 2018), companies looked to whether they had substantial physical presence in a state. As I often tell clients, consider where you have “boots on the ground”, in terms of employees, contractors, offices, and inventory (see more below) – to name the more common nexus creators. Once nexus is established, the company may be subject to the filing of income tax returns, the collection and remittance of sales tax and filing of returns, employer payroll taxes and employee withholding, and myriad other taxes which may be imposed by the state or local entities. A challenge that some foreign companies face is that they don’t realize how many different state and local agencies there are (in addition to the US federal government).