Withdrawing ED to RD

Hi
Yes I am trying to withdraw my early decision. I got into a state college at home which is one third of the tuition of the Private ED school. The acceptance was a surprise. wonder if I have to tell reason to the ED school why I want to withdraw. I mean I didn’t apply anywhere else for ED. However the state college has better ranking than the ED school and way cheaper tuition. I wonder if I can just tell them “Sorry can i just go to RD?”. I didn’t get ED offer of admission yet.
Do I need a really good reason?

You don’t need a reason if you have not received a decision from your ED school yet - you can say something vague, like “due to recent events, I am requesting my application be changed from ED to RD.”

Are they going to put me in the “blacklist”?

@Fonz93 No. you will not be thought of badly. Students situations change for various reasons.

Lots of students move to the RD list, or even withdraw the application entirely. Just contact the admissions office and ask them to move you.