Why records matter
Good records help you monitor business progress, prepare financial statements, identify income sources, track deductible expenses, prepare tax returns, and support items reported on returns if audited. The IRS does not require any particular form of recordkeeping, but the records must be sufficient to establish the income, deductions, and credits claimed.
Choosing an entity
Pub 583 walks through the four primary entity choices for a new business: sole proprietorship, partnership, corporation, and LLC. The choice affects tax filing forms, self-employment tax exposure, owner liability protection, ability to add owners, and exit complexity.
EIN application
A federal Employer Identification Number is required if you have employees, operate as a corporation or partnership, or have certain types of trusts. Sole proprietors with no employees may use their SSN, but using an EIN reduces SSN exposure to vendors and contractors who request a W-9.
Bookkeeping basics
Maintain a separate business bank account, retain receipts for all deductible expenses, log mileage contemporaneously, and reconcile your books to your bank statements monthly. The IRS recommends keeping records for 3 years (the normal statute of limitations) but 7 years if you claim a worthless securities deduction or a loss from worthless debt, and indefinitely if you never file or file a fraudulent return.
Sample recordkeeping system
Pub 583 includes sample journals, ledgers, and bank reconciliations suitable for a very small cash-basis business. Modern accounting software replaces most of these manual records, but understanding the underlying flows (transactions → journal → ledger → trial balance → financials → tax return) helps when troubleshooting bookkeeping problems.
Companion forms and schedules
Most IRS publications are written to support one or more specific forms. The publication's first chapter typically lists the forms it covers, and the form instructions cross-reference the publication. Used together, the form instructions and the publication answer most line-by-line questions. When they conflict — which is rare but happens, usually after a mid-year legislative change — the form instructions generally win, because they are revised more frequently and reflect the most current IRS interpretation.