It was my impression that I had to mail it in when I owed money in 2018. When I filed Turbo Tax online in early 2020 (for 2019), I believe the e-filing process with the state took care of it. It appears, from the City of Detroit and State of Michigan linked tax website, that the state is now electronically processing all Detroit returns. It would be nice if a Turbo Tax / Intuit expert would comment on this to be sure we understood it.
