The latest state to act to force out of state sellers to collect sales tax is Utah. In a special session, the Utah Legislature passed SB 2001 which conforms the state’s rules requiring out of state sellers to file with Utah with the provisions found in South Dakota’s law.
Utah’s triggers for filing by an out of state seller will conform to South Dakota’s, effective on January 1, 2019. As well, the previous rule that allowed sellers who voluntarily collected Utah tax to retain 18% of the tax collected will be repealed effective on the same date.
As is true under the South Dakota law, a seller must begin collecting and remitting Utah sales tax if the total sales exceed $100,000 or engages in 200 transactions in either the current or prior calendar year.
 https://www.streamlinedsalestax.org/index.php?page=utah, July 20, 2018