Antibody drug conjugates (ADCs) have been successful in oncology, mainly due to enhanced specificity and reduced side effects that burden highly cytotoxic cancer drugs. The interest to apply the ADC approach in non-oncological indications has been growing in recent years as other properties of molecules, such as efficacy and pharmacokinetics, can also be improved through conjugation to an antibody. While the most advanced ADC therapies in other therapeutic areas depend heavily on the progress made in oncology, new ideas and applications are also emerging. In this review, we summarize the current knowledge and development status of ADC candidates in non-oncological areas. We focus primarily on immunology and infectious disease but other therapeutic areas, such as atherosclerosis and ophthalmology, are also discussed.