The Colorado 112 form is a crucial document for C corporations operating within the state. This form facilitates the filing of corporate income tax returns, ensuring compliance with state tax regulations. The form includes several related documents, such as the DR 0112, which is the main income tax return, and the DR 0158-C, used for requesting an extension of time to file. Corporations must be aware of the due dates, typically falling on the fifteenth day of the fourth month after the end of their tax year, with extensions available for an additional six months. However, it is important to note that while an extension to file is granted, it does not extend the deadline for tax payments. Failure to meet payment deadlines can result in penalties and interest. Additionally, the form encompasses various schedules, including the Schedule RF for receipts factor apportionment and the Schedule C for Colorado affiliations. Proper mailing addresses for submitting these forms, with and without payment, are provided to ensure accurate processing by the Colorado Department of Revenue. Understanding the nuances of the Colorado 112 form is essential for corporations to maintain their tax obligations and avoid unnecessary complications.