Interstate 55 in Mississippi

Interstate 55 is a major north–south Interstate Highway that serves the middle of the United States. It runs from I-10 in Laplace, Louisiana—about west of New Orleans—to U.S. Highway 41 in Chicago, Illinois. In Mississippi, it runs for about, entering the state at the Louisiana state line near Osyka and leaving at the Tennessee state line near Southaven, just south of Memphis.

Route description

The highway parallels US 51 during its trek roughly through the center of the Magnolia State. North of Jackson, the Interstate runs east of the bluffs of the Mississippi Delta.

Louisiana to Jackson

The highway enters the state through Pike County and almost immediately has an interchange with MS 584. For the next few miles, there is a weigh station, rest area, and exits to Chatawa and MS 568.
The freeway interchanges MS 48 near Magnolia before entering McComb. In McComb, MS 24 and US 98 interchanges I-55, with US 98 becoming concurrent with I-55 through McComb, before splitting off in Summit at a cloverleaf interchange. The interstate continues north through Pike County and eventually enters Lincoln County.
I-55 has an exit leading to Bogue Chitto and soon after crosses into Brookhaven having an interchange with US 84. The route continues north for a few miles before entering Copiah County. I-55 has an exit for Wesson and an exit for MS 28 in Hazlehurst. The highway travels a few miles north and has a small interchange near Gallman. I-55 now runs along the western side of Crystal Springs before having an interchange with MS 27 and US 51, starting a concurrency with I-55 and US 51. A few miles north, the two routes enter Hinds County and quickly passes through Terry having an exit to the town. Soon after, the concurrent routes enter Byram, widening to six lanes at an interchange and soon after entering Jackson.

Jackson area

In Jackson, the highway has a few exits before becoming concurrent with I-20 east and US 49 south at a Y-shaped interchange, with US 51 continuing north as State St. Shortly after, the three routes cross the Pearl River into Rankin County, where I-55 splits off from I-20 and US 49 at a major interchange. I-55 quickly crosses the Pearl River and enters Hinds County and the city of Jackson once more. The interstates continues on the east side of Jackson as wide freeway with frequent exits, including one with MS 25. Eventually, the highway has an interchange with County Line Rd and enters Madison County and the city of Ridgeland. I-55 crosses over US 51 and has a T-interchange with I-220. The highway quickly passes through Ridgeland and enters Madison, where I-55 meets MS 463 at a Single-point urban interchange before shortening to a four lane interstate. The interstate has two exits in Gluckstadt. As I-55 enters Canton, the highway has a cloverleaf interchange including Collector-distributor lanes with
Nissan Parkway. Shortly after, I-55 has an interchange with MS 22. North of Canton, the route interchanges MS 16 and quickly crosses the Big Black River into Yazoo County.

Central Mississippi

The highway travels through rural areas, having exits to Vaughan and MS 432 before entering Holmes County. Passing through thick forests, the interstate has interchanges with MS 17,
MS 14, and a road leading to Holmes County State Park. The highway eventually interchanges MS 12 and has an exit to West not long after. After traveling for some miles, the route enters Carroll County. In Carroll County, I-55 continues through rural forests and has an interchange with MS 35 and MS 430 near Vaiden. Shortly after, the highway crosses into Montgomery County before entering Winona and having an interchange with US 82. I-55 quickly goes back into Carroll County to have an interchange with MS 404 and shortly after enters Grenada County. The interstate travels north for a few miles and eventually enters the city of Grenada, having an interchange with MS 8 and MS 7 where MS 7 joins I-55 in a concurrency. On the outskirts of Grenada, US 51 crosses to the west side of the interstate before MS 7 splits off at an interchange. The highway quickly enters Yalobusha County and travels through rural forests for several miles. The route interchanges MS 330 near Tillatoba and has an interchange with MS 32 outside of Oakland. Soon after, the highway runs west of Enid Lake and eventually enters Panola County

North Mississippi

The route travels north for a few miles and has an exit to Pope and Courtland. I-55 continues north through forests before entering Batesville. Here, the highway has an interchange with US 278 and MS 6 before having an interchange with MS 35 on the north side of the city. Now, the route crosses the Tallahatchie River and travels north to Sardis, where the highway interchanges MS 315. A few mile north, the interstate has an interchange with MS 310 near Como before entering Tate County. I-55 quickly enters Senatobia and has an interchange with MS 4. Soon after, the route passes through Coldwater where I-55 interchanges MS 306. A few miles ahead, the highway crosses the Coldwater River (Mississippi) into DeSoto County. The interstate travels north for several miles before entering Hernando and having an exit with MS 304 Scenic. North of Hernando, I-55 meets I-269 and I-69 at a cloverleaf interchange, where I-69 joins I-55 in a concurrency to the state lane. The two routes continue north to reach Southaven, where I—55/I-69 interchanges with MS 302 at a Partial cloverleaf interchange and widens to ten lanes. The two interstates travel as an urban freeway through Southaven until reaching an exit with Stateline Rd and shortly after, entering the state of Tennessee and the city of Memphis.

History

I-55 in Mississippi has gone through many reconstruction projects including one that widened the highway from Siwell Road in Byram to McDowell Road. The project began construction in 2014 and was completed in 2018. Another major project is the reconstruction of I-55 from Old Agency Road to MS 463 in Madison, adding more lanes, frontage roads and a new exit to Madison Ave and Colony Park Blvd.
In Desoto County, there is a proposed project that will reconstruct I-55 between Southaven and Hernando, split into 3 phases. The first phase is to widen the interstate to ten lanes from Goodman Road and Church Road along with interchange improvements. The second phase goes from Church Road to I-269, including a new interchange with Star Landing Road, widening the highway to ten lanes. The third and final phase goes from I-269 to Commerce St. in Hernando, improving the interchange between them. The highway would be six lanes in this section. As of October 2025, there is no official estimate of when the project will start.