Preheat the air fryer to 400 degrees Fahrenheit (205 degrees Celsius).
Spread the frozen hash brown patties in a single layer with a little space between them.
Air fry for 5 minutes. Flip the patties with a spatula, season with salt and pepper if using, and air fry for 4 more minutes until golden and crispy.
For crispier hash browns, keep cooking in 1-minute increments until they reach your favorite texture.
Serve right away with ketchup, if using.
Video
Notes
Don't skip preheating, so the patties cook evenly.
Don't overcrowd the basket. The hot air needs room to circulate, so cook in batches if needed.
Cook time depends on how thick your patties are and your air fryer. Thinner patties may be done a minute sooner and thicker ones may need 10 to 12 minutes.
Flipping is optional in a toaster-oven style air fryer, but it gives the most even color.
For extra crunch, lightly spray both sides of the patties with cooking spray before air frying.
Store leftovers in an airtight container in the fridge for 2 to 3 days and reheat in the air fryer for 2 to 3 minutes.
Nutrition is an estimate for 1 store-bought frozen patty without the optional oil spray, salt or ketchup. Sodium varies a lot by brand, so check your package label.