Is it haram to stand while urinating?

The Prophet ﷺ usually sat

Aisha said that if anyone tells you the Prophet ﷺ urinated standing, don't believe them, because he only urinated sitting (Jami' at-Tirmidhi 12). She was describing what she saw at home, and that was his normal habit.

But Hudhayfah reported that the Prophet ﷺ came to a rubbish dump belonging to some people and urinated standing (Sahih al-Bukhari 224, Sahih Muslim 273). Scholars explain that he did this because of the place, perhaps it was dirty or there was nowhere to sit, and it shows standing is allowed.

What scholars say

• Majority: standing is allowed, and sitting is better because it follows his usual practice and protects from splashes.
• Some Hanafi scholars: standing without a reason is disliked (makruh), though not haram.
• All agree: if standing means urine splashes onto your clothes or body, or others can see you, you should avoid it.

The real issue: splashes

Islam takes care with urine very seriously. The Prophet ﷺ passed two graves and said both people were being punished, one of them because he didn't protect himself from his urine (Sahih al-Bukhari 218). That's why the focus is on staying clean, not on posture alone.

If a drop does land on your clothes, wash that spot before you pray. See Can I pray with a stain on my clothes?

Urinals in Western toilets

Public toilets in the UK, Europe and the USA often have open urinals. Many Muslims avoid them for two reasons:

• Privacy: your awrah may be visible to the man next to you.
• Cleaning: it's hard to clean yourself properly at a urinal.

Using a cubicle solves both. You can sit, then clean yourself with water or tissue. See Do Muslims have to use water instead of toilet paper? If you do use a urinal, stand close, use dividers, and check for splashes. Don't forget the short dua when you go in. See What dua do I say when entering the bathroom?