Negative balances can occur when a transaction posts to your account, but the settled amount is greater than your available Bento account balance.
Normally, if a merchant preauthorizes a transaction for an amount greater than the Bento account balance, the Bento card will generally be declined. However, in rare circumstances, a merchant may process a transaction without prior authorization, or more commonly, a settled amount ends up being greater than the pre-authorized amount, and there is not enough available balance in your Bento account at the time the transaction is posted.
If this occurs, your account balance will fall into a negative number, and you may be notified to load more funds into your Bento account, but you will not be charged an overdraft fee.
For example, say you have $100 available in your Bento account balance, and you ring up a $100 dinner bill. So your card is pre-authorized for $100. But since you received fantastic service, you decide to leave a $50 tip. When the restaurant transaction settles, the posted amount is actually $150. Since you only had a $100 balance, your balance would become negative (-$50)
While this does not happen often, it is important to keep track of your balance and reload funds as needed. To help track your balance, the Bento account holder can opt to receive alerts when the balance in the account falls below a certain threshold.