The smallest deposit amount you can make varies from one online brand to another. It typically lands between $5 and $10. Also, first-deposit welcome promotions generally require you to make a slightly bigger deposit, e.g. $20 to $50. However, this is not necessarily the case with all brands. In addition, you might want to deposit a higher amount at the start in order to take advantage of welcome bonus offers which MI casino and sportsbook apps will undoubtedly offer.