Can Muslims sleep in a mosque?

The Companions slept in the mosque

Abdullah ibn Umar said he used to sleep in the Prophet's ﷺ mosque when he was young and unmarried (Sahih al-Bukhari 440). One day the Prophet ﷺ found his son-in-law Ali asleep there, covered in dust, and woke him kindly with a nickname, "Get up, Abu Turab" (father of dust) (Sahih al-Bukhari 441). The poor Companions known as the people of the Suffah lived in a shaded part of the mosque (Sahih al-Bukhari 442). So the mosque was never a place where a nap was out of place.

I'tikaf: staying in the mosque

I'tikaf means staying in the mosque for worship. The Prophet ﷺ did it in the last ten days of Ramadan every year until he died (Sahih al-Bukhari 2026), and the Quran mentions it directly:

Many mosques in Europe and the USA open overnight for i'tikaf in Ramadan, with a sign-up sheet and a space for sisters.

Etiquette if you sleep there

• Ask first. Most Western mosques lock up after Isha for safety and insurance reasons. Respect that; it's their right to set rules.
• Keep it tidy. Use a mat or sleeping bag, don't block the prayer rows, and pack up before Fajr.
• Wet dreams: a person in a state of major impurity (janabah) shouldn't stay in the prayer hall, according to most scholars (based on Quran 4:43). Leave quietly and take a ghusl.
• Wudu: deep sleep breaks wudu, so renew it before you pray. See Does sleeping break wudu?
• Bedtime adhkar: the usual sleep sunnahs apply here too. See What should I say before sleeping?

Short naps and travelers

A short rest between prayers, or a traveler resting before moving on, is fine. Try not to fall asleep while the khutbah is going on, and if you nod off, scholars recommend moving to a different spot to wake yourself up.