SR 28 begins just south of Jasper at an interchange with I-24/SR 27 in Marion County. It then goes north as a 4-lane divided highway to have an interchange with US 41/US 64/US 72/SR 2, where it becomes concurrent with US 41, in Jasper before bypassing downtown to the east and continuing north and narrowing to a 2-lane. Between both of the aforementioned interchanges, SR 28 has an unsigned concurrency with SR 27. The highway then has an intersection with unsigned SR 150, where US 41 splits off, before leaving Jasper and continuing north. It then travels up the Sequatchie Valley, parallel to the Sequatchie River, and passes through Sequatchie before entering Whitwell at an intersection with SR 283. It then has an intersection with SR 108 before going through downtown and leaving Whitwell to go down a long, narrow valley full of farmland. SR 28 then crosses into Sequatchie County.
Sequatchie County
SR 28 then goes north to leave the Sequatchie River before it enters Dunlap and has a y-intersection with US 127/SR 8. From this point on, SR 28 is the unsigned companion route of US 127 from Dunlap to the state line at Static. US 127/SR 8/SR 28 then go north through downtown to an interchange with SR 111, with SR 8 splitting off here to go west on SR 111. US 127/SR 28 then go through some farmland before entering Bledsoe County.
US 127/SR 28 immediately have an intersection with Vandever Road, which is a connector to SR 282 and Lake Tansi Village. They then go through more farmland before passing by Cumberland Mountain State Park and having an intersection with SR 419. They then come to a y-intersection with SR 68, where US 127/SR 28 turn northeast to enter Crossville. They then intersect SR 392 before entering downtown and having an intersection with US 70/SR 1/SR 101. They then pass through downtown before widening to a 4-lane and junctioning with SR 298. US 127/SR 28 then have an intersection with US 70N/SR 24 before going through Crossville's main business district before crossing the Obed River and coming to an interchange with I-40. US 127/SR 28 then leave Crossville and continue north through more farmland. They then cross into Fentress County via a couple of sharp switchbacks, in order to negotiate a bridge over Clear Creek.
Fentress County
US 127/SR 28 then go through more farmland before entering Clarkrange to have an intersection with SR 62. US 127/SR 28 then passes through Clarkrange before having an intersection with SR 85 and entering Grimsley. They then pass through Grimsley before widening to a 4-lane and intersecting SR 296 west of Allardt. They then enter Jamestown and bypass downtown to the east and have an interchange with SR 52 before having one with SR 154. They then leave Jamestown, at the other end of Main Street, and continue north and narrowing to a 2-lane. They then pass through Sgt. Alvin C. York State Historic Park and Pall Mall before crossing into Pickett County.
Pickett County
They intersect with SR 325 and then SR 295 before entering Static and intersecting SR 111 immediately before crossing the state line into Kentucky, with SR 28 ending here and US 127 continuing into Kentucky.
