While running a business like running a hotel offering multiple services to their customers, one is always required to pay tax to the government for running these businesses. One of the most common tax is CT600. If you think what is CT600, company tax return is essential in order to pay taxes on your earnings. This tax payment is needed for all enterprises, from small businesses to huge corporations, and is referred to as corporation tax. Your CT600 must be submitted to HMRC within 12 months after the end of the accounting period covered by the return. This is usually the same as the financial year covered by your annual accounts, although it may be different if this is your company's first year of operation.