The fight against disinformation is one of the major battles that journalism has had to face in recent years, especially after the coronavirus pandemic. As a counterbalance, “fact-checker” news media –platforms that have an important role in verifying whether or not the content circulating is true and that have harnessed the benefits of social networks, in spite of the difficulties inherent in these applications, to disseminate reliable and fact-checked content– have emerged. This study aims to explore how 10 prominent fact-checking accounts in Ibero-America use the social network Instagram to debunk false information, focusing in particular on the field of science and health. Applying a content analysis method using a checklist with quantitative and qualitative indicators, a total corpus of 240 posts from the first half of 2022 was obtained. The results allow us to determine which type of hoax has been used most as well as whether Twitter, Facebook, and WhatsApp are used for its dissemination. It was observed that health topics are the ones that attract the greatest interest from fact-checker accounts when it comes to creating fact-checks, and they tend to use static images or slide mode as opposed to video. In addition, they tend to use formal language in their presentation. This study also reveals that there were no instances of interaction with followers. While fact-checker accounts extensively use Instagram owing to its visual capabilities, they do not necessarily take advantage of its graphic potential. In addition, it was concluded that coronavirus is still a relevant topic for fact-checker media outlets, which must constantly refute the hoaxes that are mostly spread through social networks.