Most studies on crowding perception have focused on terrestrial natural areas and, to a lesser extent, on marine areas. The cenotes (sinkholes) of the Yucatán Peninsula are flooded caves that comprise one of the largest freshwater reserves in Mexico, and their use is rapidly changing from agricultural-livestock to tourism-recreational. Determining crowding indicators and standards has proven to be an effective tool in making the social dimension of carrying capacity in tourism-recreational sites operative and contributing to its sustainable management. This study used normative theory and the visual method to identify the crowding standards of visitors to two cenotes located in the community of San Antonio Mulix in Yucatán and to compare these standards in three types of visitors: local, national and international. Likewise, willingness to pay (WTP) for each type of visitor was identified and its correlation to perceived crowding was analyzed. The results found that visitor acceptability in both cenotes decreased as the number of people increased. In both cenotes international visitors have the most restricted crowding acceptability levels and are those who are willing to pay a higher entry fee. Finally, the results are discussed in the framework of better management of the cenotes.