This module focuses on the revenue section of Form 1120 page 1 and the flow of cost of goods sold into gross profit. Learners review how gross receipts, returns and allowances, net receipts, and COGS should be entered, computed, and validated in OneSource. The module emphasizes independent recomputation, support-based review, and confirmation that page 1 amounts flow correctly through the return.

This module covers common supporting income items, major deduction categories, and the payments and credits areas of the corporate return. Learners practice mapping amounts to the correct Form 1120 lines, identifying likely OneSource input locations, and confirming that each item is supported and classified correctly. The module reinforces a structured workflow for reviewing how non-operating income, deductions, payments, and credits affect the overall return.

This module centers on Schedule M-1 book-to-tax reconciliation, prior-year comparison, and final error resolution. Learners review how book income is reconciled to taxable income, how to classify and document year-over-year variances, and how to investigate non-zero tie-outs caused by duplication, omission, or misclassification. The module concludes with a practical final review approach that helps confirm the return is structurally sound and ready for reviewer handoff.