Owners of residential property will see their taxes go up and the owners of industrial property will see their taxes go down in 2012, under the single tax rate approved by Selectmen Monday night.

Mattapoisett residential property owners will see an average $445 increase on tax bills with an assessment increase of 5.3 percent for 2012.

Commercial and industrial values have gone down an average of .62 percent and 13.9 percent, respectively, with a commercial bill increase of $181 and industrial bill decrease of $315.

The changes are reflections of a couple of things: Calendar years 2009 and 2010 showed a decrease in real estate sales and larger-than-normal growth in commercial classes.

The Board of Assessors, which determines these numbers, is required to followed these calendar years.

The Board of Selectmen approved the single tax rate of $11.26 for 2012 Monday night, meaning the residential and commercial/industrial/personal property classes will pay the same rate.

If the Board had approved a split tax rate—which puts more taxes on the commercial classes—residential bills would have gone down an average of $90, with businesses seeing an average increase of $450 in taxes.

“The shift isn’t worth it,” said Principal Assessor Kathleen Costello. “I believe it would hurt our small businesses.”

Town Administrator Mike Gagne said Mattapoisett is still doing well compared to other towns in the state.

Costello said notifications have already been mailed.