The highway heads east as Mineral Spring Avenue, a two-lane road with frequent center turn lanes, through a densely populated suburban area.

The missing movement is provided via Route 246 (Charles Avenue), which the highway meets east of the interchange and where the center turn lane ceases.

The highway continues east on two-lane Exchange Street across the Blackstone River and by the Pawtucket Armory to Broadway.

From the eastern end of the one-way pair, Route 15 follows Armistice Street, which is two lanes undivided to a commercial area at its intersection with George Bennett Highway.

Route 15 intersects US 1A (Newport Avenue) and becomes an undivided highway as it passes Slater Park and crosses the Ten Mile River.