Invasive species - American bullfrog (Lithobates catesbeianus) in Flanders, Belgium (Post 2018) is a species occurrence dataset published by the Research Institute for Nature and Forest (INBO). The dataset contains over 24600 occurrences (40 % of which are American bullfrogs) sampled between 2019 until now, in the months April to October. The occurrences were collected through fieldwork and the framework of bullfrog management. Captured bullfrogs were almost always removed from the environment and humanely killed, while the other occurrences are recorded bycatch, which were released upon catch (see bibliography for detailed descriptions of the methods). Therefore, caution is advised when using these data for trend analysis, distribution range calculation, or other. Issues with the dataset can be reported at https://github.com/inbo/sk-analyse We strongly believe an open attitude is essential for tackling the IAS problem (Groom et al. 2015). To allow anyone to use this dataset, we have released the data to the public domain under a Creative Commons Zero waiver (http://creativecommons.org/publicdomain/zero/1.0/). We would appreciate it however if you read and follow these norms for data use (http://www.inbo.be/en/norms-for-data-use) and provide a link to the original dataset (https://doi.org/10.15468/daf62d) whenever possible. If you use these data for a scientific paper, please cite the dataset following the applicable citation norms and/or consider us for co-authorship. We are always interested to know how you have used or visualized the data, or to provide more information, so please contact us via the contact information provided in the metadata, opendata@inbo.be or https://twitter.com/LifeWatchINBO. Data from 2010 to 2018 can be found here: https://doi.org/10.15468/2hqkqn