It is not haram for a man to urinate standing up, but it is Sunnah for him to urinate sitting down. ‘Aishah said: “Whoever tells you that the Prophet used to urinate standing up, do not believe him. He only ever used to urinate sitting down.” This is more concealing, and it reduces the risk of any drops of urine splashing up onto him.

Muslim bathroom etiquette includes: not facing the qiblah, not touching the penis with the right hand, not removing impurity with the right hand, answering the call of nature sitting, concealing oneself from the sight of others, reciting dhikr when entering or leaving the toilet, and not urinating into stagnant water.