From Vinton, it heads north and east towards Urbana where it meets Interstate 380 (I-380) and Iowa 27, the Avenue of the Saints highway.

As it traverses through the east-central part of the state, Iowa 150 mostly passes through farmland where acreages and farmsteads dot the landscape.

Between Fayette and West Union, part of the route forms the western leg of the River Bluffs Scenic Byway, which passes through Iowa's "Little Switzerland" region.

US 218 comes up from the south and turns west at the intersection while Iowa 150 begins heading north along C Street.

North of Vinton, the highway passes a small airport surrounded by fields and then curves to the east for a few miles.

The highway heads due north, only passing a few houses until it reaches US 20 south of Independence.

The two routes head through Oelwein along Frederick Avenue and split a couple miles north of town.

[5] The highway turns east very briefly and returns heading north until it reaches Fayette County Road C33 (CR C33).

Between Fayette and West Union, the highway forms the western leg of the River Bluffs Scenic Byway, through the area known locally as "Little Switzerland".

[6] In West Union, the route meets the western end of Iowa 56 on the south side and then US 18 in the heart of town.

[11][12] Through Cedar Rapids, the highway entered from the north along Center Point Road NE.

[13] From Cedar Rapids, the route continued south and east by overlapping US 30 and Iowa 38 to Tipton.

[16] During the 1950s, as today's highway system was beginning to take shape, Iowa 150 was rerouted a couple times in Cedar Rapids.

Instead of continuing south to Coe College, it turned east at Collins Road and connected with US 151 and Iowa 64 near the eastern city limits.

It then followed those two routes to downtown Marion, where it turned south onto a road which headed southeast towards Mount Vernon.

[26] In the 1980s, Iowa 150 near Oelwein was rerouted onto a new section of highway along the former right-of-way of the recently liquidated Rock Island Railroad.

[30] On June 11, 2008, about 2 miles (3.2 km) of Iowa 150 north of Vinton closed for a few months after flood waters from the Cedar River destroyed the roadway.

By the end of the month, one lane the bridge over the Cedar River had reopened to local traffic and farmers.

The washed-out section of highway was rebuilt, repaved, and reopened on September 10, almost three months after it closed.

Iowa 920 headed east towards Walker, where the highway skirted the edge of town by curving to the south.

[37] In the southern part of town, where Center Point Road turned south, Iowa 920 ended.

The committee identified over 700 miles (1,100 km) of state highways, including Iowa 920, which could be turned over to local jurisdictions.

[38] Most of the committee's recommendations were accepted and on July 1, 2003, Iowa 920 and over 600 miles (970 km) of state highways were turned over to the counties or local jurisdictions.

[26] It was turned over to Linn County by 1986 as sections of I-380, which was being built adjacent to Center Point Road, opened to traffic.