Importance Sunscreen use has known benefits, including decreasing the risk of developing skin cancer and photoaging. Previous studies have reported that the amount of sunscreen used decreased with increased unit price and that individuals underapply sunscreen. Objective To assess how the cost of recommended sunscreen use varies depending on unit price and the other sun protective behaviors. Design and Setting In this economic evaluation study conducted from July 14 to August 31, 2025, sunscreen application costs were calculated based on recommended application amounts, use of other sun protection strategies, and 2025 sunscreen prices. Main Outcomes and Measures The primary outcome was the annual cost of applying sunscreen based on recommended application amounts, use of other sun protection strategies, and 2025 sunscreen prices from an online retailer. Results For sunscreens with similar ingredients and sun protection factor ratings, the unit price of sunscreen varied by up to 17.5-fold across 3 sunscreens. Cost per application varied from $0.04 to $3.79 depending on wearing different combinations of typical clothing, whereas 1 year of sunscreen use was estimated to cost between $39.28 and $1429.42, a 36-fold difference, depending on unit price and other sun protective strategies used. A single week of sunscreen use at the beach, assuming 2 applications a day, costs approximately $6.57 to $135.82, depending on whether wearing shorts or a bikini and sunscreen unit price. Conclusions and Relevance These findings suggest that the cost of applying sunscreen at the recommended amounts varies significantly depending on unit price and the concurrent use of other sun protective strategies. Decreasing the potential cost by encouraging the use of other sun protective strategies and lower-priced sunscreens could facilitate compliance and reduction in the risk of developing skin cancers.