Multiple guidelines and standards for design of accessible toilets in India result in inconsistent data for design. This, in turn, hinders the adoption of environmental accommodations such as grab-bars in toilets and compromises on the safety and wellbeing of all users including older adults. Therefore, this pilot study used a full-scale simulation protocol to compare the usability of toilet grab-bar heights specified by four different accessibility guidelines and standards. Twelve adult participants performed usability trials in a full-scale toilet simulation with grab-bars installed at heights of 600, 650, 675, 700 and 750 mm, respectively, located on either side of a water closet with a seat-height of 400 mm. A validated, two-step, usability rating scale was used to assess usability of the grab-bar heights. Results suggest that the grab-bar mounting height between 650–675 mm was preferred by participants. While this finding is in tune with the relevant ISO standard, it is significantly lower than the 725–750 mm grab-bar mounting height advocated by the Harmonized Guidelines & Standards for Universal Accessibility in India, 2021. These findings underline the need to undertake full-scale simulation studies to create the evidence-base that would help to develop guidelines and standards for design of accessible toilets in India. In future, full-scale simulation studies with a larger sample of representative users including older adults and persons-with-disabilities is needed to confirm the validity of these initial findings.