Year-End Accounting Checklist for Small Business

Every January, two kinds of business owners call their accountant. One sends clean books and gets a tax return. The other sends a shoebox — digital or literal — and gets a bill for cleanup, a later filing, and a few missed deductions nobody can reconstruct. The difference isn't talent; it's a checklist run in November and December instead of a scramble in March. Here's the year-end close, organized by month, tuned for closing out 2026.

What should you clean up in November?

November is for the slow-moving items — the ones that are painful to fix after December 31:

1. Chase receivables now. Review open invoices and push collections — December collections land in this year's cash, and January conversations about February invoices go nowhere.
2. Collect W-9s before the last check. Any contractor you might need to 1099 should have a W-9 on file before final payment — your only leverage disappears when the last check clears.
3. Clear the "Uncategorized" account. Every transaction sitting in Uncategorized or Ask My Accountant is a deduction at risk. Work the pile down while you still remember what things were.
4. Review unpaid bills. Decide what to pay in December versus January — for cash-basis businesses, that's a real timing lever on this year's deductions.
5. Look at inventory early. If you carry stock, flag the obsolete and damaged items now so the December 31 count is a count, not an archaeology project.

What has to happen in December?

December items are date-locked — miss them and the option expires with the year:

1. Reconcile every account — bank, credit card, loan, and payment processors (the one everyone forgets; payout timing and fees hide there).
2. Count inventory at December 31. Your cost of goods sold is only as accurate as this number.
3. Place new equipment in service by December 31 if you want the deduction this year — in service means installed and usable, not ordered. With 100% bonus depreciation now permanent, there's no expiring-provision panic, but the which-year question still moves real money.
4. Run bonuses through payroll before the final run. Year-end bonuses are wages — they need withholding, not a handwritten check on December 30.
5. S corporation owners: get health premiums into your W-2. Premiums the company paid for a more-than-2% shareholder must be included in Box 1 of your W-2 to preserve the personal deduction. Call your payroll provider mid-December; this is genuinely hard to fix after W-2s are issued.
6. Review estimated taxes against actual profit. A strong or weak Q4 changes the January payment you should make.
7. Fund what must be funded by December 31 — most employee retirement deferrals ride on the last payroll of the year.

What's due in January 2027?

1. Final December reconciliation — then lock or close the period in your software so the numbers your tax preparer gets stop moving.
2. W-2s to employees and the SSA by February 1, 2027 (January 31 falls on a Sunday).
3. 1099-NEC for contractors by the same date — with a genuinely new rule: for payments made in 2026, the reporting threshold rose from $600 to $2,000 per contractor. Fewer forms to file, but note the fine print — contractors owe tax on every dollar regardless, and some states kept lower thresholds.
4. Q4 estimated tax payment by January 15, 2027.
5. Hand off the tax package — financial statements, reconciliation reports, asset purchases, loan statements, payroll summaries — early. Preparers do their best work in February, not April 14.

Which deadlines actually matter?

What should you actually look at once the books close?

Closing the books isn't for the IRS — it's the one time a year you get honest numbers. Spend an hour on four questions: How did the P&L compare to plan, line by line? Which direction is gross margin moving, and why? What does AR aging say about who's really funding your customers? And how many months of runway does the cash balance represent at the current burn? A hedged illustration of why this pays: during a December close, a retail client's reconciliations commonly surface things like duplicate software subscriptions, a processor charging a stale rate, and unbilled December work — call it a few thousand dollars found in an afternoon. Results vary, but "reconciliation finds money" is one of the most reliable patterns in bookkeeping.

What are the most common year-end mistakes?

1. Reconciling in a rush — plugging differences instead of finding them, which quietly poisons next year's books.
2. Booking loan payments as expenses — only the interest is deductible; the principal portion overstates expenses and understates income.
3. Treating owner draws as payroll (or vice versa) — the tax treatment differs completely by entity type.
4. Missing 1099s — or assuming the new $2,000 federal threshold applies to your state's rules.
5. Skipping the inventory count and rolling forward last year's number.
6. Leaving the books unlocked after handing them off, so the return and the ledger silently diverge.
7. Doing all of this in March — every item above gets more expensive with distance.

If it's already behind — months unreconciled, a year of Uncategorized, no asset schedule — that's the most common starting point new clients bring us, not an embarrassment. Problems come here to get solved. Our bookkeeping service includes year-end close as standard, catch-up work is quoted flat on our pricing page, and if you want the numbers to drive decisions — not just a tax return — that's what our advisory team is for.

FAQ

My books are six months behind. Where do I start?

Start with bank and credit card reconciliations, oldest month first — categorization arguments are pointless until the accounts tie to the statements. A focused catch-up usually takes days, not months, and it's a fixed-scope project any competent bookkeeper can quote flat.

Do I send a 1099 to a contractor I paid $1,500 in 2026?

Federally, generally no — the threshold for 2026 payments is $2,000. But the contractor still owes tax on it, some states require reporting at lower amounts, and you can file voluntarily. Also remember payments made by credit card or payment platforms are reported by the processor (1099-K), not by you.

Cash or accrual — does it change my year-end work?

The mechanics are the same (reconcile, count, document), but timing levers differ: cash-basis businesses can shift income and deductions by controlling December payments and deposits; accrual businesses look harder at receivables, payables, and unearned revenue cut-offs. Know which basis your return uses before playing with December timing.

When should year-end close actually be finished?

A realistic target: reconciliations and adjustments done by mid-January, tax package delivered by early February. Businesses that close monthly all year finish in days; the checklist above is mostly hard for businesses doing twelve months of bookkeeping in one bite.

Can't my CPA just fix everything in March?

They can — at hourly cleanup rates, under deadline pressure, with the timing levers (equipment, bonuses, W-2 items, December payments) already expired. Cleanup recovers accuracy; it can't recover options. That's the whole argument for the November start.

Reviewed by the WAYG tax team · Updated July 2026