Removing hair from the head or any other part of the body does not break one's wudu (ablution). This is the position clarified by Shaykh Abd al-Aziz ibn Baz.

The Shaykh explained that the matters that nullify wudu are well-known and established by the textual evidence of the Qur'an and Sunnah. These include things such as passing wind, urine, or stool; deep sleep that leads to unawareness; touching the private parts with desire; and eating camel meat.

As for actions like cutting one's hair, trimming the moustache, clipping the nails, or removing hair from the armpits or pubic area, there is no evidence (daleel) to indicate that they invalidate the state of purity. The same applies to dry skin that is peeled off and does not cause bleeding. A person who does any of these things after performing wudu remains in a state of tahara (purity) and their wudu is still valid. They may pray with that wudu without needing to repeat it.

The principle in Islamic jurisprudence is that a matter remains upon its original ruling—in this case, the validity of wudu—until there is clear evidence to prove a change. Since no such evidence exists for the removal of hair, wudu remains intact.