What is Schedule C?
Definition Schedule C reports the profit or loss from a sole proprietorship or single-member LLC and attaches to the owner's Form 1040. It lists business revenue and deductible expenses, and the resulting net profit flows to the 1040 where it is also subject to self-employment tax. Accurate expense categorization here directly affects both income tax and self-employment tax.
For self-employed clients, Schedule C is where good bookkeeping turns into tax savings, and where sloppy records can trigger scrutiny.