There’s a few types of caulk used for stucco crack repair and which you choose hinges on the type of damage. For example, you’ll find that acrylic caulks are most common for smaller jobs like hairline cracks. Polyurethane caulking on the other hand is used for deep holes or cracks due to its sealing properties. Brands like DAP and Quikrete are common choices with reviews to back their performance.