CHICAGO ( TheStreet) -- For many small businesses, 2009 was the end of the road. With consumer spending down dramatically, owners had no choice but to shut down operations, close up storefronts and sell off equipment.But an owner's obligations don't end when the employees have been let go and the office is empty. If you closed your business any time during 2009, you still have to file a final annual tax return. How do you inform the IRS you're no longer in business? That depends on the size and nature of your company. Corporations must file Form 966, "Corporate Dissolution or Liquidation," within 30 days of the decision to dissolve or liquidate the company's stock. Partnerships that file Form 1065, "U.S. Return of Partnership Income," can check the "Final Return" box near the top of the first page. But many small businesses are sole proprietorships, whose owners report their business profits or losses by filing Schedule C with their individual tax returns. The owner can simply write "Final Return" at the top of his or her 2009 Schedule C to let the IRS know that the company has closed. Depending on the size of your business and where you conducted it, you'll also have other forms to file. Just as it's relatively easy to start up a business if you're the one and only employee, it's also quicker to shut down a one-person shop. If you were the sole proprietor, worked from home and didn't purchase any new equipment to do your job, you won't have to do anything but file that last Schedule C. If, however, you rented a small office and bought a computer, printer and office furniture, then your business had assets, and the IRS expects you to document how you disposed of them. If you sold the assets, you'll have to fill out Form 8594, "Asset Acquisition Statement," detailing the fair-market value and the sales price for each asset. The only good news is that you'll get a tax break if your sale price was below market value, as was often the case last year.