NY 156 begins crossing through a more densely wooded area of Guilderland, soon reaching the junction with Gardner Road, where it is more residential. The route soon crosses into the town of New Scotland, changing names to Altamont Road, reaching a junction with CR 307 (Picard Road). Running east through New Scotland, NY 156 crosses the southern end of CR 202 (Meadowdale Road) before turning southeast once again. Crossing through multiple farms, NY 156 winds east into the residential section of the village of Voorheesville. Still known as Altamont Road, NY 156 bends southeast past a junction with CR 208 (School Road).