Your monthly GI Bill payment may be less than your monthly rate for one of these reasons:

• You attended classes for only part of the month. Classes often begin and end somewhere in the middle of a month, instead of on the first and last day of a month. So we’ll base your payment only on the part of the month you attend classes. For example, if your monthly rate is $800, and your classes start on August 19, we’ll pay you $320 for August 19 to 31.
  Note: Your monthly rate is based on a 30-day period. The rate for a month that has 31 days (like October) is the same as the rate for a month with 30 days (like September). 
• We overpaid you at some point in the past. If we discover an overpayment, we’ll need to pay you less for one or more payments. 
• You reduced your enrollment hours during the term. If you stopped taking some of your classes—or reduced your training time—after you received your award letter, we’ll need to adjust the benefit payment amount.

Check the current payment rates