Provincial Trunk Highway 20A (PTH 20A) is a 5.3-kilometre (3.3 mi) long provincial highway spur in the Parkland Region of the Canadian province of Manitoba.

Its main purpose is to provide access to Dauphin for any traffic using PTH 20.

[1] Unlike most alternate highways, which would have been the original route of the main highway before it was realigned and redesignated, the southern leg of PTH 20A (1st Avenue N.E.)

Although it acts as the eastern boundary for its city limits, PTH 20 never enters Dauphin itself.

From this point, it travels northeast along Main Street N. and River Avenue E. for two kilometres (1.2 miles) back to its northern terminus with PTH 20.