Short answer: yes, in many Jain monastic traditions, monks (muni/acharya/sadhu) do not take regular baths as part of their ascetic vows.

• Digambara (sky-clad) monks: they typically do not bathe. Their discipline emphasizes total renunciation of worldly comforts, including regular washing, to avoid harming small life and to stay focused on spiritual practice.
• Śvetāmbara (white-robed) monks: they also follow strict cleanliness rules, but their practice is generally described as more restrained than ordinary bathing. They may perform minimal cleansing and alms-based routines, but they refrain from ordinary bath practices as part of renunciation.

Key idea across both traditions: the emphasis is on ahimsa (non-violence) and detachment from bodily comforts. Bathing is avoided because it could harm tiny life forms in water and because physical comfort is considered a distraction from spiritual aims.

If you’d like, I can share more about the specific practices of Digambara vs. Śvetāmbara in their daily routines, or provide a traditional text reference. You can read more here