1 (9 inch) vegan pie shell (such as Wholly Wholesome®)
Preheat oven to 375 degrees F (190 degrees C).
Combine almond milk, sugar, and arrowroot powder in a blender; blend until sugar and arrowroot are completely dissolved. Add pumpkin puree, pumpkin pie spice, and salt; blend until smooth. Pour into the pie shell. Cover edges of the pie shell with aluminum foil.
Bake in the preheated oven until center is set, about 40 minutes.
Cool pie to room temperature, about 1 hour. Refrigerate until firm, 8 hours to overnight.