Banks sometimes close accounts that have a zero balance after a certain number of days (either 30, 60, 90, 180, a year, etc). For that reason, be sure to always leave $1 in any account that you want to remain open. Leaving $.01 is probably safe too, but I usually leave $1.
Two readers have been discussing that Chase automatically closes a bank account with zero balance after 60 days (which is something I don’t remember hearing in the past). In their case, this resulted in them losing out on a large bonus that was supposed to get deposited to the account.
The rule is to always leave some small amount of money in an account that you want to keep. For example, since Marcus seems to offer existing-customer deposit bonuses from time to time, I don’t want that account closed, so I leave $1 in the account. Accounts that I don’t care for, but never got around to closing, I empty out and hope they close out themselves.
Related: Complete List Of Ways To Close Bank Accounts At Each Bank