> ## Documentation Index > Fetch the complete documentation index at: https://docs.budgetbandit.io/llms.txt > Use this file to discover all available pages before exploring further. # Rolling money forward > How a category's leftover or overspent balance carries into next month, and the Rollover switch that controls it. When the month changes, each category decides what to do with the money still in it. Leftover money can carry forward, so a category builds up over time. Each category controls this with its **Rollover** switch. ## Rollover on: the balance carries forward With Rollover turned on for a category, whatever is left in its Available amount at month's end carries into the next month and stacks on top of what you assign there. Fund Gifts with $50 a month and spend nothing for two months, and by the third month Gifts holds $100 before you assign anything new. This is how sinking funds work — savings for an annual bill, a vacation, a car repair fund. The category quietly accumulates until you need it. Overspending carries too. If a category with Rollover on goes negative, that shortfall follows it into next month and comes out of what you assign there. The budget makes you answer for it rather than letting it vanish. ## Rollover off: the category resets With Rollover turned off, the category starts fresh each month. Leftover money does not carry — it returns to your control to assign elsewhere. Overspending does not carry either. This fits categories that should reset every month: a monthly "fun money" or dining allowance you do not want to bank. Whatever is left at month's end is simply gone from that category, available to assign again. ## Choosing per category Rollover is set on each category, so you mix the two: * **On** for sinking funds and savings — anything that should accumulate. Car maintenance, gifts, annual insurance, a travel fund. * **Off** for monthly allowances you want to reset — discretionary spending you do not want to roll into a bigger number next month. You change it from the category's menu on the Budget page. ## Credit-card overspending is treated differently Overspending on a credit card you have not funded is not the same as spending cash you did not have. The cash never left your accounts — you owe it on the card. So credit overspending does not roll forward as a category shortfall the way cash overspending does. It shows up on the card's Payment category instead, as a shortfall to fund. See [How credit cards work](/concepts/how-credit-cards-work). ## Income does not roll into a category Income categories do not carry a balance forward. Income flows into [Ready to Assign](/concepts/ready-to-assign), where it becomes money you assign in the month it arrives. ## Next Fix a red category before it follows you into next month. Give a category a goal so it refills itself each month.