I would also like to have this feature. I came here to suggest it and then found someone else already had. It seems like the needed data is already available in CalendarBudget… which is the cool thing about CalendarBudget. It knows what the balance is on each date.
When you pay the full balance on your credit card every month you are paying the previous month’s closing balance. That should correspond (and does, in my experience) to the CalendarBudget balance for the card on my accounts closing date.
Here is how I see it working. We would need to store our closing date and payment due date with the account information. So, say my payment due date is the 25th and my closing date is the 28th. A full-pay transaction could be automatically entered on the 25th with whatever my credit card balance was on the 28th of the previous month. Viola! And, even cooler, take the balance shown on the next 28th of the month and enter it as payment on the 25th after that.
One trick would be for CalendarBudget to revert to manual mode if I overwrote the payment amount. Say, I can’t afford the full payment this month and edit the payment amount for this month. I wouldn’t want CB to keep changing it back.
But this seems like a awesome feature to me. Assuming this automatic entry was made two months into the future I would see a credit card purchase today hit my check book balance a month and half (or whatever) from now.