What is the $1 charge that appears in my online Account Activity?

On debit card purchases, merchants may request a temporary hold on your account for a specified sum of money when the merchant does not know the exact amount of the purchase at the time the card is authorized. The amount of the temporary hold may be less than or more than the actual amount of your purchase. Some common transactions where this occurs involve purchases of gasoline, hotel rooms, or meals at restaurants. When this happens, our processing system cannot determine that the amount of the hold exceeds the actual amount of your purchase. This temporary hold, and the amount charged to your account, will eventually be adjusted to the actual amount of your purchase, but it could be three calendar days, or even longer in some cases, before the adjustment is made. Until the adjustment is made, the amount of funds in your account available for other transactions will be reduced by the amount of the temporary hold.