Stir refried beans in a saucepan over medium-low heat until hot, 2 to 4 minutes.
Warm tortilla in a skillet over low heat until softened, 1 to 2 minutes. Transfer tortilla to a plate.
Layer lettuce onto tortilla. Spread warmed refried beans, avocado slices, and pico de gallo on top of lettuce. Roll tortilla around the fillings into a burrito shape.