"Ittekimasu" is a common phrase used when leaving home or a place to indicate that one will be back. It expresses the intention to return and can also be used as a way of saying goodbye.
Related terms
ただいま (tadaima): Tadaima is a phrase used upon returning home. It means "I'm back."
行ってらっしゃい (itterasshai): Itterasshai is a phrase used to see someone off when they leave. It means "Take care" or "Have a safe trip."
おかえりなさい (okaerinasai): Okaerinasai is a phrase used to welcome someone back. It means "Welcome back."
"いってきます (I'm leaving/See you later)" also found in: