Yes, you should still file a business income tax return.
If you have closed your business, file a business income tax return that shows no activity and make sure that you mark the "final return" box on the first page of the return. This will let the IRS know that there will be no future income tax filings for your business. You should also contact your state taxing authority to determine what requirements they have for closing your business.
If you have not closed your business and plan to resume operations in the future, you should continue to file income tax returns for the busniess until it is closed and you file a final return. You can file a return showing no activity (also known as a 0 return.)
If you do not file a return for a business that has not yet been reported as closed, it is very likely that you will receive notices, and possibly incur penalties, for that business.
