There have been 10 business routes of US Highway 127 in the state of Michigan. The business routes are all sections of state trunkline highway that run through the central business districts of their respective towns connecting them to the mainline highway outside of those downtown areas. These various business routes were formerly part of the routing of US Highway 127 (US 127) or its predecessor in Central Michigan, US 27, before the construction of highway bypasses. The southern two, in Jackson and Mason were previously parts of US 127, while seven of the northern eight (Lansing, St. Johns, Ithaca, St. Louis, Mount Pleasant, Clare and Harrison) were originally part of US 27, a highway which was replaced on its northern end by US 127 in 2002. The business loop through Alma was once numbered US 27A.

In the late 1920s, US 27 was shifted to run through St. Louis instead of Alma, and the former route was renumbered US 27A. US 127 was realigned near Mason in the mid-1940s, and a business loop was created out of the former routing there. A similar bypass of Jackson in the late 1950s also spawned a business loop. In the early 1960s, a new expressway (later freeway) for US 27 through Central Michigan led to the creation of several business loops. Other bypasses opened in the 1980s and 1990s and created the last two business loops. The 2002 extension of US 127 to replace US 27 also led to the redesignation of business loops to their current monikers. __TOC__

Jackson

Business US Highway 127 (Bus. US 127) is a business loop of US 127 through Jackson that is wholly concurrent with M-50. Its southern end is at an interchange in a rural section of Summit Township. From exit 34 on US 127, the business loop runs north and northwesterly, crossing the Grand River. North of the river, the roadway is bounded by businesses as it runs along Cooper Street through residential areas on the southeastern side of Jackson. In the downtown area, Bus. US 127/M-50 merges with Business Loop Interstate 94 (BL I-94) and splits to follow a one-way pairing of streets that form a loop through downtown. Northbound traffic continues along the eastern side of this loop on Cooper Street and crosses the Grand River again. At the intersection with Michigan Avenue, BL I-94/Bus. US 127/M-50 turns westward onto Louis Glick Highway around the northern side of downtown. The business loop crosses the Grand River a third and final time along Louis Glick. On the western side of downtown, the business loop angles southwesterly as Louis Glick Highway merges into Michigan Avenue. (At the same time, the southern half of the one-way loop, Washington Street, also splits from Michigan Avenue.) BL I-94/Bus. US 127/M-50 follows Michigan Avenue westward through residential neighborhoods to an intersection with West Avenue, where Bus. US 127/M-50 turns northward, separating from BL I-94 (Michigan Avenue). As the business loop approaches its parent highway, it transitions into a commercial area. The northern terminus of Bus. US 127 is at the same interchange northwest of Jackson in Blackman Township where the US 127 and I-94 freeways merge.

Jackson was first bypassed on its eastern side around 1959 with a new US 127 freeway. At that time, the former routing of US 127 through downtown was redesignated Bus. US 127. In 1964, several changes were made to the business routes in downtown Jackson. Southbound Bus. US 127 traffic was shifted off Michigan Avenue along Blackstone Street to Washington Avenue, and from there it ran along Washington to Francis Street and back to Michigan Avenue. The northbound traffic was shifted north at Mechanic Street to Pearl Street, continuing until turning south at Blackstone back to Michigan Avenue. The eastern end was updated further in 1968 to use Louis Glick Highway to connect to the northern half of the loop around downtown to Michigan Avenue. A set of connector streets on the western side of the downtown loop opened in November 1969 to streamline the flow of traffic further resulting in the last changes to the BL I-94 routing in Jackson. Southbound traffic was redirected to the connector on Michigan Avenue just east of Third Street. This connector curved south then east to Washington Avenue near First Street. Louis Glick Highway was extended west from Blackstone curving south to merge into Michigan.

Major intersections

Mason

Business US Highway 127 (Bus. US 127) was a business loop that ran through downtown Mason. It started at an intersection on the southern edge of the city where US 127 split from Hull Road to bypass downtown Mason to the west. From there, the business loop ran northward along Hull Road, becoming Jefferson Street. At the intersection with M-36 (Ash Street), Bus. US 127 turned westward and ran concurrently with M-36. After four blocks and a crossing of the Sycamore Creek, Bus. US 127/M-36 turned northward on Cedar Street to Columbia Avenue and then turned westward along Columbia to an intersection with US 127 west of downtown.

The state bypassed Mason around 1946, building a new highway to the west of downtown, and the former route of US 127 through downtown was redesignated Bus. US 127. This business loop existed until 1964. At that time, the bypass around Mason was upgraded to a full freeway with an interchange at Cedar Street northwest of downtown. Two segments of highway were turned over to local control at this time: the southern half of Bus. US 127 along Hull Road and Jefferson Street as well as the section of Bus. US 127/M-36 along Columbia Avenue. M-36 was extended northward along Cedar Street to the new interchange, and the Bus. US 127 designation was decommissioned.

Major intersections

Lansing

Business US Highway 127 (Bus. US 127) is a business route in Lansing that is unsigned. The trunkline starts at an intersection with Business Loop Interstate 96 (BL I-96) at the corner of Cedar and North streets in the northern part of the city. Marked as Old US 27 on maps, the business route follows Cedar Street northeasterly and transitions onto East Street. The highway runs through residential areas on the north side of Lansing. Along the route of Bus. US 127, the highway is immediately bounded by some commercial businesses. At Sheridan Road, the highway crosses from Ingham County into Clinton County and continues as a road named Old US 27. Bus. US 127 continues through suburban southern Clinton County, still bordered by businesses and residential neighborhoods, northward to an interchange with I-69 in DeWitt Township.

In 1984, part of the northern freeway bypass of Lansing opened as I-69. At that time, US 27 was rerouted to follow the new freeway. The former routing of US 27 through downtown Lansing was redesignated Bus. US 27 as a business loop along Lansing Road, I-496 and BL I-96 at this time. Eight years later, the last section of I-69 was completed in Michigan. Afterwards, Bus. US 27 was truncated to the interchange between BL I-96/Capitol Loop and I-496, and the state reconfigured it into a business spur into downtown Lansing from the north.

In 1999, MDOT petitioned the American Association of State Highway and Transportation Officials to decommission the US 27 designation in the state; the change was approved on April 16, 1999. The state waited until 2002 to make the change. After the change was implemented, Bus. US 27 was renumbered to Bus. US 127 as with all of the other similar business routes in the state. However, unlike the other new Bus. US 127s, this one had no connection to US 127, its new parent highway. MDOT has retained the business route as an unsigned trunkline designation ever since.

Major intersections

St. Johns

Business US Highway 127 (Bus. US 127) starts at the Price Road interchange along US 127 south of St. Johns. From here, Bus. US 127 follows Price Road to the former US 27 and turns north along South Old US 27. In the city of St Johns, it is known as Whittemore Street and intersects M-21 (State Street). Bus. US 127 continues north on North Old US 27 to its northern terminus. The northern terminus of Bus. US 127 nearly coincides with the northern end of the existing US 127 freeway in Clinton County. Approximately one-half mile (0.8 km) north of the Bus. US 127 interchange north of St. Johns, the US 127 freeway merges back onto its former alignment to proceed northerly into Gratiot County.

The St. Johns Bypass on US 27 opened on August 31, 1998, and the former route of the highway through downtown was redesignated Bus. US 27 afterward. In 1999, MDOT petitioned AASHTO to decommission the US 27 designation in the state; the change was approved on April 16, 1999. The state waited until 2002 to make the change. After the change was implemented, Bus. US 27 was renumbered to Bus. US 127 as with all of the other similar business routes in the state to reflect the new parent highway designation.

Major intersections

Ithaca

Business US Highway 127 (Bus. US 127) is a business loop that runs from an interchange on US 127 on the southern Ithaca city limits through downtown and back to the freeway north of the city. The southern end is at exit 117 on US 127, and from there, the business loop runs westward along Center Street through a cluster of businesses adjacent to the freeway interchange. Further west, Bus. US 127 passes through residential neighborhoods to enter downtown Ithaca. At Main Street, the business loop turns northward one block to Emerson, then turns westward one block along Emerson to Pine River Street, bypassing downtown Ithaca. From there, Bus. US 127 turns northward along the former route of US 27 through town. North of downtown, the highway passes through another residential area before exiting Ithaca. North of town, the business loop passes a golf course before turning eastward a short distance along Polk Road to connect to the freeway.

An expressway through Gratiot County opened in late 1961, and US 27 was rerouted to follow it, bypassing Ithaca to the east. The former route of US 27 along Center and Pine River streets in Ithaca was designated Bus. US 27 at this time. On April 26, 1973, the state transferred control over one block of Center Street west of Main Street and one block of Pine River Street south of Emerson Street. At the same time, the city transferred control of one block each of Main and Emerson streets. In 1999, MDOT petitioned AASHTO to decommission the US 27 designation in the state; the change was approved on April 16, 1999. The state waited until 2002 to make the change. After the change was implemented, Bus. US 27 was renumbered to Bus. US 127 as with all of the other similar business routes in the state to reflect the new parent highway designation.

Major intersections

Alma