MacRumors reported on October 7, 2026 that some Apple Watch Series 12 and Ultra 4 owners have described skin irritation on its forums and Reddit. The complaints include a burning sensation and redness under the watch's sensor area. These are user reports, not a confirmed defect or a measured rate of affected devices.
The report discusses changes to the watches' sensors and heart-rate readings, but says it is unknown whether those changes are responsible. Skin irritation has also been reported with earlier Apple Watch models. The available evidence does not establish a cause, the scale of the issue or a model-wide safety finding.
Apple's general support page on wearing an Apple Watch says reactions can arise from allergies, environmental factors and extended exposure to irritants such as soap or sweat. It also notes that a band worn too tightly can irritate skin, while a loose band can cause rubbing. That page is general wear guidance; we have not verified a new advisory issued specifically for Series 12 or Ultra 4.
Apple recommends a snug but comfortable fit, with room for skin to breathe, and keeping the watch, bands and skin clean and dry. Its guidance suggests consulting a physician before putting the watch back on if redness, swelling, itchiness or other irritation occurs.
MacRumors says some owners reported improvement after cleaning or an adjustment period, while others returned their watches. Those individual experiences do not establish that one fix will work for everyone. Buyers should treat this as a report of complaints with an unresolved cause, rather than a recall or confirmed hardware fault.