Year-End Checklist: 12 Things to Do Before December 31, 2026

Most of year end happens in January. A short list only counts if it happens by December 31. Count the parts on the trucks and in the shop on the 31st. Put any truck or equipment you're buying in service by the 31st. Pay the bills you want to deduct, if you're on the cash method. Send a W-9 request to every contractor still missing a tax ID. Write down the odometer readings. Get an S corporation owner's health insurance onto the last payroll. And reconcile the books through November now, so December is the only month left in January.

Here is the list in the order to do it, then what comes after the 31st.

In November: get the year current

1. Reconcile every account through November. Bank, cards, the line of credit and any loan. A December close on top of eleven reconciled months is a day's work. On top of eleven unreconciled ones, it's a cleanup. If the books are months behind, the cleanup checklist is the place to start.

2. List every contractor you paid this year, and how. Checks, ACH and Zelle count toward the $2,000 line for 2026; card and PayPal payments don't. Anyone who will cross $2,000 needs a W-9 and, in January, a 1099-NEC. The 1099 threshold post has the rules, and who gets a 1099 covers LLCs and corporations.

3. Look at the year's profit and the tax set aside. Eleven months of reconciled books give you a real estimate of the year. That tells you whether the fourth estimate needs to be bigger, and whether a purchase you were planning anyway is worth making in December rather than January. How much to set aside walks through the math.

In December: the things with a December 31 deadline

4. Send a W-9 request to everyone still missing one, in writing, by December 31. For contractors who haven't given you a tax ID, the IRS's penalty-relief rules expect an initial request when you started working together and a first annual request by December 31 of the year you paid them. Making it on time protects you if the 1099 goes out without a tax ID in January. The W-9 guide has the request emails.

5. Put the truck or equipment in service, if you're buying it. A vehicle or machine counts for 2026 only if it's ready and available for its job by December 31. Ordered isn't enough, and neither is paid for if it's still at the upfitter. If it is in service, 100% bonus depreciation or section 179 can usually deduct it in full. Buying a work truck before year end has the weight rule and the catches.

6. Write down your expensing policy for 2027. The de minimis safe harbor lets you expense items up to $2,500 each, but the policy has to be in place at the start of the year. Write one line now: "We expense items costing $2,500 or less per invoice or item." It doesn't have to be in writing without audited financial statements, but a dated line is easy proof.

7. Pay the bills you want to deduct, if you're on the cash method. On the cash method, a bill paid December 30 is a 2026 deduction and the same bill paid January 4 is a 2027 one. Money customers pay you in December is 2026 income. On the accrual method, none of this moves anything: expenses count when incurred and income when earned.

8. Get an S corporation owner's health insurance onto the last payroll. If the S corporation pays health insurance for an owner with more than 2%, the premiums belong in the owner's W-2 wages. Tell your payroll provider before the final run, not after the W-2s print. The what your CPA needs post covers the rest of officer pay.

9. Check the payroll data before the W-2s. Addresses, Social Security numbers, and benefits that go on the W-2. New for 2026: qualified overtime is reported separately, in box 12 with code TT. Ask your payroll provider how it will fill it in. The details are in tax deductions for trade contractors.

10. C corporations: the fourth estimate is due December 15. A calendar-year C corporation's last 2026 estimate is due December 15, 2026, before the year ends. Owners of S corporations, partnerships and sole proprietorships pay theirs on January 15, 2027. Quarterly estimated taxes has the safe harbor.

On December 31: the counts

11. Count the parts. What's on each truck and in the shop on December 31 is inventory, not an expense, under most accounting methods. Count it that day or as close as you can, and keep the count sheet. Texas shops need the same list for the business personal property rendition, which is based on what you owned on January 1. The Texas rendition post has the $125,000 exemption.

12. Write down every vehicle's odometer reading. The year's business miles start from a number, and the IRS expects records for each vehicle. A photo of each dashboard on December 31, sent to yourself, is enough.

In January: what comes after

The usual January 31 deadline is a Sunday in 2027, so the 1099 and W-2 dates move to Monday, February 1. To file the 1099s without your own IRS filer code, see how to file 1099s online for 2026.

How Poof runs year end

In Poof, December is a close like the other eleven: 19 tasks with due dates, 15 of them ticked by the books themselves when the books prove them. Bank feeds bring the transactions in as they happen, so reconciling November is matching, not typing. You count each truck from your phone, and Poof knows what went on jobs and what went missing.

For 1099s, the W-9 board shows who's in, who's been asked and whose link ran out, and anyone still missing shows up in Needs Attention from December 1. In December, Poof tells you your 1099s are ready to look over, and in January a card flags checks written in December that cleared in January. Approve the forms with one signature and Poof files them; the first 3 forms each year are free.

The taxes calendar has every date above on the day it really falls, with a reminder two weeks ahead, and the year-end package puts the year in one PDF for your CPA. Poof prepares and reminds; it never files a return or pays the IRS.

*General information, not tax advice; your CPA has the final word.*

*Written by Austin Semple, a former controller: two years in audit, seven running the books for small businesses, and the founder of Poof. Poof runs December as a close with a checklist the books tick off themselves. Start free, no card required.*