Most banking institutions offer the valuable service of free online alerts to let you know exactly what is happening on your account.
These alerts can be sent by text to your cell phone or by email or even both.
They can help you avoid late fee, over the limit fees and especially notify you of fraudulent activity. They can give you your account balance; notify you when a payment is due and when a payment has been posted to your account.
You can set them up according to your needs. You can arrange to get notified when any purchase exceeds a certain amount or when your remaining balance hits a certain level.
The alerts are usually free from the bank but your cell phone provider may charge you a texting fee.