Preheat your air fryer to 350°F (175°C) for a few minutes.
Lay out four slices of bread. Spread a thin layer of softened butter or margarine on one side of each slice of bread.
Place a slice of cheese between two slices of bread, with the buttered sides facing outward. This forms your grilled cheese sandwich.
Carefully place the assembled sandwiches in the air fryer basket, making sure they are not touching.
Cook the sandwiches in the air fryer at 350°F (175°C) for about 4-6 minutes. Check them after 3 minutes to ensure they are cooking evenly.
Open the air fryer and carefully flip the sandwiches using tongs. Continue cooking for an additional 3-5 minutes, or until the bread is golden brown and the cheese is melted and gooey.
Once the grilled cheese sandwiches are golden and the cheese is melted, carefully remove them from the air fryer.Let them cool for a minute or two before slicing and serving.