Tennessee has three taxes that apply to sales: State Tax, Local Tax, and the State Single Article Tax.
The general State Tax rate is 7.00%. The Local Tax rate varies by county and/or city. There is an additional 2.75% State Single Article Tax that applies on any single item sold in excess of $1,600, but not more than $3,200.
To accommodate this you must create three sales tax definitions in The Edge. See the articles in this section for the steps to set this up.
Read more about Tennessee Sales tax on the TN Department of Revenue website.