Form 1120 Page 1: The Income Section, Line by Line

Line 1a — Gross receipts or sales: Total revenue from the corp's primary business activity — before any returns, refunds, or discounts. Include cash and credit sales, and don't net anything against it. If the corp is a service business, this is total billings collected + billed but not yet collected (if accrual method).

Line 1b — Returns and allowances: Refunds paid to customers and price reductions granted after the sale. Sales tax collected from customers is NEVER on Line 1 — it's a liability to the state, not the corp's income.

Line 1c — Net (1a minus 1b): This is the number that starts the return. Rental income from a real-estate C-corp goes on Line 6 (Gross rents), NOT Line 1. Interest earned goes on Line 5. Only revenue from the primary trade or business lives on Line 1.

Line 2 — Cost of goods sold: Filled in only if the corp sells physical products (retail, wholesale, manufacturing). Pure service corps skip this line entirely.

COGS is computed on Form 1125-A and flows here. The COGS formula is:
Beginning inventory + Purchases + Cost of labor + Additional §263A costs + Other costs – Ending inventory = COGS

Line 3 — Gross profit = Line 1c – Line 2. This is the true 'operating' number for a product-based corp.

Chapter 3 covers Form 1125-A and inventory in depth. The most common preparer mistake here: forgetting to reduce beginning inventory by any obsolete or written-off items before completing the schedule.

Line 4 — Dividends and inclusions (from Schedule C): Total dividends received from other corporations, gross before the dividends-received deduction. If the corp owns 5,000 shares of Ford stock and received $8,200 in dividends, that $8,200 lands on Line 4. Chapter 7 covers Schedule C and the DRD in depth.

Line 5 — Interest: All taxable interest earned by the corp — bank accounts, notes receivable, bond interest. Municipal bond interest (federally tax-exempt) is NOT here — it goes on Schedule K.

Line 6 — Gross rents: Rental income if renting real property is NOT the corp's primary business. If it IS the corp's primary business, rents still go here (this is a common source of confusion).

Line 7 — Gross royalties: Royalties from patents, copyrights, and mineral rights.

Line 8 — Capital gain net income (Schedule D): Net gain from sale of capital assets. If it's a NET LOSS, it stays on Schedule D and gets carried forward — C-corps cannot deduct capital losses against ordinary income like individuals can.

Line 9 — Net gain or (loss) from Form 4797: Sale of business assets used in the trade or business (equipment, real estate) that produce §1231 or ordinary gain/loss.

Line 10 — Other income: The catch-all. Cancellation of debt income, insurance proceeds in excess of basis, prizes, kickbacks — everything that doesn't fit elsewhere. Attach a statement listing each item.

Line 11 — Total income = Sum of Lines 3, 4, 5, 6, 7, 8, 9, and 10.

This is the number the IRS considers the corporation's gross income for the year. Everything below Line 11 is deductions (Lines 12–29), leading to Line 30 taxable income.

Line 11 also matters for a bunch of thresholds you'll encounter — such as whether the corp qualifies as a 'small business taxpayer' for §263A UNICAP relief ($30 million average gross receipts) or is subject to §163(j) interest expense limits.