As Tom stated above, my understanding also boils down to this: Your physical location is the determining factor. So if you are physically working in MD (even though you are a resident of another state) you will owe MD taxes on the income earned there. This has also been my experience in the past with physically working in one state and residing in another. You should be able to get your employer to withold MD taxes or you can also outright pay MD estimated taxes, either one. Otherwise, MD is likely to penalize you if nothing is being paid throughout the year of you working in MD. I don't know how MA handles the taxes you are having to pay to MD. Some states will give a credit back to you for income earned and taxed in another state. I am not familiar with how MA would handle that but hope that I have helped, otherwise. My situation was different because I was not physically located in MD, but earning $ from a MD source via remote work only.
