Can I go back to sleep after suhoor?

Sleep doesn't harm your fast

There's nothing in Islam against sleeping after suhoor. Your fast stays valid whether you are awake or asleep. Many Muslims in Europe and the USA eat suhoor, pray Fajr, and then sleep for an hour or two before work or school, especially when Fajr is very early in summer.

Suhoor itself is a blessed meal, and the Quran sets its end time:

Pray Fajr before you sleep

Zayd ibn Thabit said they ate suhoor with the Prophet ﷺ and then he stood up for the prayer, and the gap between the two was about the time it takes to recite fifty verses (Sahih al-Bukhari 1921). So the Sunnah is to eat suhoor late, close to Fajr, and pray soon after.

• Wait for the Fajr time to come in, then pray. Don't pray before the time starts.
• If you're very sleepy, set two alarms, or ask a family member to wake you.
• If you oversleep by mistake, pray as soon as you wake up. That's not a sin.

If you often miss suhoor altogether, see What if I sleep through suhoor?

Is sleeping after Fajr disliked?

Some scholars considered sleeping between Fajr and sunrise less ideal, because the early morning is a blessed time for dhikr and work. The Prophet ﷺ would often stay sitting where he prayed Fajr until the sun had risen (Sahih Muslim 670). But this is a recommendation, not a rule. If you need the sleep to function at work or care for your children, sleeping after Fajr is fine. Even a few minutes of morning adhkar before you lie down captures some of that blessing.

Balance your sleep

Going back to sleep after suhoor is healthy; sleeping the whole fasting day away is not the spirit of Ramadan. See Can I sleep all day while fasting? If you're not sure about your wudu after a nap, see Does sleeping break wudu?