Is it Sunnah to have Suhoor on the day of Eid al-Fitr?

It is not from the Sunnah to have suhoor on the night of Eid. Rather, the Sunnah on the day of Eid al-Fitr is to eat before going out for prayer, based on the hadith narrated by Anas: "The Prophet (peace be upon him) would not go out on the day of Eid al-Fitr until he had eaten some dates, and he would eat them in odd numbers." The wisdom behind this is so that no one would think that fasting is obligatory until after the Eid prayer, or as a prompt to obey Allah's command to break the fast after the obligation of fasting has ended.