In the Budget column, assign dollars to each category until your Available to Budget amount is $0.
In the sample below, we started out with $1000 Available to Budget and budgeted $200 into Groceries and $100 into Restaurants. That total is shown in the line Budgeted in May. $300 has been budgeted so far. This is subtracted from Available to Budget and there is still $700 which needs to be assigned to categories.
Typically, no. All dollars should be assigned to a category. However some people save for their Buffer by letting some money roll into next month.
When you don’t budget all of the money that is Available to Budget, that same amount appears in next month’s header under Not budgeted in (previous month). This will become a part of the Available to Budget number for the next month.