Form 1120 - ENGAGE CPAs

Form 1120 is the business tax return you'll need to file if you own a C-Corporation. This is where you'll show the C-Corporation's business income and any deductible businesses expenses that will be used to reduce that income. Based on the income reported, the business will pay tax on that income at the corporate level. Remember, this is the only entity type that pays tax to the IRS at the business level. So there are no K-1s needed because you don’t need to worry about business income on your personal tax return if you own a C-Corporation.
But wait, there’s more! The only way for an owner of a C-Corp to pay themselves is by W2 wages and dividends, which are both subject to income tax at the personal level. This is where double taxation talk comes in!
Form 1120 is due to be filed every year by April 15th, the same day as the personal tax returns are due, but you also have the option for file a six month extension.