SR 149 begins at an intersection with
SR 130, just north of the
Chicago Fort Wayne and Eastern Railroad and
Norfolk Southern Railroad tracks. The road heads north as a two-lane highway, passing through rural farmland with some houses. The highway has traffic lights at
U.S. Route 6 (US 6). The route crosses under the
Indiana Toll Road and has an at-grade crossing with the
CSX Transportation railroad tracks. The road crosses another set of CSX Railroad tracks and has a traffic light at
US 20. North of US 20, the highway becomes a four-lane undivided highway, with a wide median. The route crosses over
Interstate 94 (I–94). The route curves northwest, becoming a four-lane undivided highway and having an intersection with
US 12. No segment of State Road 149 in Indiana that is included in the
National Highway System (NHS). The NHS is a network of highways that are identified as being most important for the economy, mobility and defense of the nation. The highway is maintained by the
Indiana Department of Transportation (INDOT) like all other state roads in the state. The department tracks the traffic volumes along all state roads as a part of its maintenance responsibilities using a metric called
average annual daily traffic (AADT). This measurement is a calculation of the traffic level along a segment of roadway for any average day of the year. In 2010, INDOT figured that lowest traffic levels were 5,299 vehicles and 94 commercial vehicles used the highway daily between US 20 and US 12. The peak traffic volumes were 12,783 vehicles and 491 commercial vehicles AADT along the section of SR 149 between Lenburg Road and US 20. ==Major intersections==