If you incorporate in Delaware, but will be doing business in another state, you will still need to register in the other state(s) as a foreign business entity. In addition, you will be required to file periodic reports in Delaware, as well as those states where you do business. Moreover, Delaware requires that you regularly submit franchise taxes, even if you are paying those taxes to the state(s) in which you are already doing business. If you’re looking for specifics take a look at this helpful pdf from Wolters Kluwer:.
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