How to See a Remaining iTunes Balanceby David Nield
You can check the balance of your iTunes account through iTunes on your computer or via an iOS device. Both the iTunes desktop client and the iTunes Store app on iOS will prompt you for your Apple ID and username before your balance is displayed. Note that if your iTunes balance is currently zero, nothing will be displayed in any of the locations.
If you have iTunes installed on your Windows or Mac computer, you can click the "iTunes Store" button in iTunes and your balance is displayed at the top of the Store page next to your registered email address. If you haven't yet logged into the Store, click "Sign In" and enter your Apple ID and password. Select your email address to see more details about your account, including the registered payment methods.
On an iOS Device
To check your iTunes balance on iOS, tap "iTunes Store" on the home screen and then scroll down the front page to the bottom to see your Apple ID and current account balance. If you haven't yet signed in using your Apple ID and password, tap "Sign In" to enter your account credentials. You can also view your current balance by tapping on the Apple ID link in the "iTunes & App Store" section of the Settings app.