Maine sales tax rates are changing effective October 1, 2013. The 5% rate will increase to 5.5%; the 7% rate will increase to 8% (the 10% rate does not change.)
Consequently, the state is requiring annual filers to prepare two returns this year, one for the period through September 30th due on October 15, 2013 and one for the period October 1 through December 31 due on January 15, 2014.
If you have questions you may call the state at 207-624-9693 or email sales.tax@maine.gov.