"Whoever narrated to you that the Prophet would urinate while standing; then do not believe him. He would not urinate except while squatting." .
Jami` at-Tirmidhi Book 1, Hadith 12
← Previous Hadith "One day I climbed on Hafsah's house, and I saw the Prophet relieving himself while facing Ash-Sham, with his back toward the Ka'bah."

Jami` at-Tirmidhi Book 1, Hadith 11 Next Hadith → "Allah's Messenger came to a waste area used by people, so he urinated on it while standing. I brought him the (water for) Wudu. Then I left to be away from him, but he called me until I was behind him. So he performed Wudu and wiped (Masaba) over his Khuff."

Jami` at-Tirmidhi Book 1, Hadith 13