Small Business Tax Preparation Checklist (2026)

A small business tax preparation checklist covers five buckets: the entity and its return form, income records, categorized expenses with receipts, payroll and contractor forms, and prior-year carryovers like depreciation. Texas owners add franchise and sales tax filings. Working through it before you meet your preparer shortens the engagement and makes the fee easier to estimate.

First, confirm your entity and its due date

The 2026 filing season handles the 2025 tax year, and the entity decides both the form and the deadline. For the 2025 tax year, partnerships and S corporations file by Monday, March 16, 2026, because March 15 falls on a Sunday. Sole proprietors and C corporations file by April 15, 2026.

• Sole proprietor, or single-member LLC: Schedule C, filed with your Form 1040. Due April 15, 2026, extended October 15, 2026.
• Partnership, or multi-member LLC: Form 1065. Due Monday, March 16, 2026, extended September 15, 2026. Owners receive a K-1.
• S corporation: Form 1120-S. Due Monday, March 16, 2026, extended September 15, 2026. Owners receive a K-1.
• C corporation: Form 1120. Due April 15, 2026, extended October 15, 2026.

If the entity changed during the year, or an S corporation election took effect, put that paperwork on top of the pile. Entity changes are where checklists break.

Extensions go on Form 7004, and they move the filing date, never the payment date. If a deadline in this list has already passed by the time you read this, file anyway and file soon: penalties and interest can keep growing until the return is in. The due dates on this page are checked against the IRS due-date tables that publish them, and the checking method is described on the editorial policy page.

Income records

Your preparer needs the year's gross receipts, not just the forms. Pull together:

• The accounting export or ledger for the year, even if it is messy.
• Bank and card statements for every business account.
• Processor and platform payout statements.
• Invoices or sales records.
• Every 1099 that arrived: 1099-NEC, 1099-K, or 1099-MISC.

Then match each 1099 against the deposits it should explain. When a form and the books disagree, do not guess: reconcile it now, because that mismatch is exactly what automated IRS matching catches later.

One trap: smaller platforms can skip issuing forms entirely, and payment apps only send a 1099-K when payouts cross reporting thresholds. Income counts even when no form arrives. The return reports what you were paid, forms or no forms, so your statements matter more than the envelopes.

Expense records

Sort expenses into the same groups the IRS expects to see, and attach the business purpose to each one:

• Home office and vehicle costs, including the mileage log.
• Health insurance premiums and other insurance.
• Retirement contributions made as the owner.
• Day-to-day operations: software, supplies, phone, subscriptions, professional fees.
• Big-ticket items that depreciate over time rather than deduct at once.

Each deduction needs the receipt and a line on why it was a business cost. For most expenses the IRS expects records, not a specific form, so a shoebox organized by month beats a spreadsheet nobody can trace. The full deduction list, with the form each item lands on, is in the self-employed deductions guide.

Payroll and contractor forms

If the business had employees, gather the payroll set: each employee's Form W-2 with the W-3 transmittal, the four Form 941 quarterly filings, and the annual Form 940. All of the January 31 sending deadlines should already be behind you by the time you sit down to file, so this section is mostly about collecting copies.

For contractors the form is the 1099-NEC, sent by January 31 for each person or business paid enough during the year. The threshold changed: for payments in years beginning after 2025, the form is required once a contractor is paid $2,000 or more, up from $600 before. Check your payment records against the forms you actually sent, because a missing 1099-NEC is easier to fix before the return than after.

Carryovers from last year

The 2025 return does not start from zero. Bring:

• A copy of the 2024 return, federal and state.
• The depreciation schedule, so this year's additions continue the same method.
• Any net operating loss carryforward.
• The estimated tax payments already made during the year, with dates and amounts. If you paid quarterly, the due dates and the safe harbor rules are in the quarterly estimated taxes guide.

Partnerships and S corporations should also export a balance sheet: Form 1065 and Form 1120-S generally attach Schedule L, though some small entities may skip it. Sole proprietors do not attach one.

Texas filings that ride along

Texas layers its own calendar on top of the federal one. Texas entities file an annual franchise report together with a Public Information Report, and if you hold a sales tax permit, returns go out on the filing frequency the Comptroller assigned. The thresholds, due dates, and no-tax-due rules for the current report year are walked through in the Texas franchise tax guide. Pull the franchise numbers from there rather than from memory, because the no-tax-due rules move with the calendar.

Questions to ask your preparer

These questions work whether your preparer is a CPA, an Enrolled Agent, or a non-credentialed preparer, because the answers reveal organization, not letters after a name:

• How many returns like mine did you file last year?
• Exactly which records do you want, in what format, and by when?
• Who signs and e-files the return, and when do I see the draft?
• If the IRS sends a notice on a return you prepared, what do you do?
• What does your fee cover, and what costs extra?

Asking for the document list early is the cheapest move on this page. It turns this checklist into your preparer's intake list, and it surfaces a disorganized shop before you have paid anything. Fee structures and typical ranges are covered in the tax preparer cost guide.

This checklist is the work of a few quiet afternoons. If you would rather hand it to a practice that runs it every week, the business return service describes the work, and you can book a session at armstrongtaxconsulting.com/book.

This article is for general informational purposes and does not constitute tax or legal advice. Consult a qualified professional for your specific situation.