Anas (May Allah be pleased with him) reported:
The Prophet (ﷺ) forbade us from drinking while standing. Qatadah reported: “We asked him: ‘What about eating?”‘ He said: “That is even worse, (or may be he said) more detestable.”
Another narration is: Messenger of Allah (ﷺ) reprimanded us for drinking while standing.
Abu Hurairah (May Allah be pleased with him) reported:
Messenger of Allah (ﷺ) said, “None of you should drink standing; and if any one forgets, he must vomit.”
Amr bin Shu’aib on the authority of his father and grandfather reported:
that they saw Messenger of Allah (ﷺ) drink standing, and sitting.
The last three Ahadith point out the permissibility of eating and drinking while walking or standing or sitting, but drinking in the sitting position remains the best.