Meaning/Usage: Used to tell a person that they are the one to make a decision
Explanation: "Up to" is commonly used to indicate a decision. It is common to say, "up to her," or "up to them," or "up to me."
"It's up to you, but I don't think we should bother him."
"I don't care what we do tonight, it's up to you."
"It's up to you whether we invite them to the party."
A. "What time do you think we should leave to go to the airport?"
B. "It's up to you. Our flight is at 7 o'clock."
A. "I think we should leave by 5 then."
A. "Ok. Sounds good to me."
Other Common Sentences
"You can decide."
"You can make the decision."