Transplantation of fecal microbiota (FMT) is now standard of care in treatment of recurrent Clostridioides difficile infections (rCDI). Research addresses whether FMT is also effective for other disorders associated with dysbiosis of the gut. To facilitate safe and cost-effective FMT, stool banks have been founded to provide ready-to-use FMT suspensions and to ensure quality assurance. Stool banks can operate at an institutional or regional/national level. Stool banks prepare feces suspensions of stool(s) from extensively screened healthy donors. Suspensions are quarantined at -80°C and only used for FMT after retesting of the donor. Standardization of stool banking is required because it enables stool banks to cooperate and compare their products and performance, which will provide important information for quality improvement. Ongoing and future studies with FMT should finally result in the development of standardized bacterial mixtures as microbiota modulating therapies for (r)CDI and other potential indications. Stool banks may help to facilitate these developments.