These roads typically follow along local streets often along a former US or state highway that had been replaced by an Interstate.

NMDOT has decommissioned US 85 throughout the state and no longer signs the highway along its length, as US 85 entirely follows I-25 with the single exception of the business loop in Las Vegas.

The loop begins at exit 75 of I-25 in Williamsburg, intersecting State Road 187 (NM 187), traveling northeast on Broadway Street through Truth or Consequences until meeting Main Avenue.

The routes combine and turn north on Date Street, intersecting the western terminus of NM 51.

Turning northwest, the highway intersects NM 181 and terminates at exit 79 on I-25 on the north side of Truth or Consequences.

The loop begins at exit 147 of I-25 and travels northwest along California Avenue until an intersection with the northern terminus of NM 1.

The loop begins at exit 190 on I-25 and intersects the northern terminus of NM 116 as the highway travels north along Main Street into the city.

It then went east on NM 466 (Saint Michaels Drive), cutting through the south side of Santa Fe.

The loop continues north, passing to the west of Las Vegas station served by the Southwest Chief line of Amtrak, just south of the intersection with NM 104.

Continuing north, the highway passes east of Municipal Park before terminating at NM 250 and I-25 at exit 347.

Continuing northwest, the loop intersects NM 468 and then runs closely parallel to the Interstate before merging at exit 414.

The two highways intersect NM 555 then pass east of La Mesa Park, traveling along Second Street north into the city.

The numerical values of all state highway names are followed by an alphabetic suffix, although this convention is used by the department internally and not reflected in route signage.

In addition to these, US 160 joins I-25 at Walsenburg and follows concurrently with the Interstate to Trinidad, including the portion bypassing Aguilar.

), inventoried as State Highway 25A (SH 25A), was a business route of I-25 that connected Trinidad in Las Animas County to the Interstate.

In 2009, a reconstruction project involved a replacement of the northbound viaduct crossing the Purgatoire River and more reconstruction in 2011, adding a new diamond interchange at Main Street and I-25 and replacing the antiquated ramps at Animas and University streets, which ultimately eliminated the route.

), inventoried as State Highway 25B (SH 25B), is a business spur of I-25 connecting the town of Aguilar in Las Animas County to the Interstate.

), inventoried as State Highway 25C (SH 25C), is a business loop of I-25 serving the town of Walsenburg in Huerfano County.

The loop then continues northeast along Walsen Avenue, leaving town, and intersects SH 69 before terminating at I-25 exit 52.

[16] The highways remain established by AASHTO primarily along I-25 in southern Colorado and along Walsenburg's I-25 business route.

It then turned northeast on CR 46 (Wolfensburger Road), heading back to the Interstate, and then terminated at exit 182 as Wilcox Street.

Near Cheyenne Regional Airport, the one-way streets combine and continue as Central Avenue before intersecting the southern terminus of WYO 219 at Yellowstone Road.

is a business route signed as WYO 321 and serving the town of Chugwater in southeastern Platte County.

begin on a short section of Mariposa Parkway but then turn north onto South Wheatland Highway for 0.3 miles (0.48 km).

Further north, the southern terminus of WYO 320 is intersected as the business loops become South Swanson Road.

are concurrent 4.966-mile (7.992 km) business loops serving the town of Douglas in southern Converse County.

The business route travels north, concurrent with WYO 95, into Glenrock on Deer Creek Road and then South 4th Street.

continues east out of Glenrock, intersecting the northern terminus of WYO 90 (Boxelder Road), before reaching its eastern end at exit 160 of I-25.

WYO 251 intersects the loop from the south along Wolcott and Durbin streets before US 20/US 26/US 87 depart on Yellowstone Highway and their respective business routes end.

is a business spur serving the city of Buffalo in Johnson County that runs concurrently with US 87 Bus.