Billing alerts send you an email if your monthly spending exceeds an amount you specify.
By default, billing alerts are disabled. You can opt into receiving billing alerts on the Billing page of your account.
In the Billing alerts section, click Enable Alert to open the Set billing alert window. Enter the threshold amount in the Amount box (which is set to $20 by default), then click Confirm.
When your monthly spending exceeds the amount specified, you receive an email at the email address associated with your account. You can change your email address on the Account Profile page.
To opt back out of billing alerts, in the Billing alerts section, click Edit, then click Remove Alert. In the window that opens, click Remove to confirm the removal.