Tax deadlines · 6 minute read
Most deadline lists are a wall of dates, and almost none of them apply to you. These are the ones that do if you run a construction, trades, or professional services business — what each date actually requires, and the work that has to happen weeks before it.
One thing to get straight first, because it changed and a lot of people haven't noticed.
For payments made during 2026, Form 1099-NEC reporting starts at $2,000, not $600. That figure sat at $600 for a very long time. It applies to the payments you made this year and report at the start of next.
Most of Form 1099-MISC moved to $2,000 as well. Two exceptions worth knowing: gross proceeds paid to an attorney stay at $600, and royalties stay at $10.
Before you decide this makes your January easier, three things.
It does not change anything about W-9s. You still need one from every subcontractor and vendor, and you still need it before you pay them, not after. A missing W-9 at the end of a job is how backup withholding becomes your problem rather than theirs.
It does not change state requirements, which are set separately and in some states still sit lower.
And it only helps if you can tell, per vendor, what you actually paid across the whole year. If a subcontractor's payments are spread across a card, a cheque, and two different expense accounts, you can't answer that question in January without a reconstruction. That's a bookkeeping problem that disguises itself as a tax problem, and it's most of what I get called about in the first week of February.
Nothing on this list has a form attached. It's the work that has to happen inside the tax year, because on 1 January the door closes on most of it.
Fourth-quarter estimated tax for 2026. The last instalment for the year just ended.
This is the one service businesses most often get wrong, and the reason is structural rather than careless. Estimated payments get set early in the year from last year's numbers, then a strong autumn arrives — a big job closes, a retainer scales up — and the January payment is still sized for a version of the business that stopped existing in September. The underpayment doesn't surface until the return is prepared, by which time interest has been accruing quietly for months.
If your last few months looked materially different from your first few, that payment deserves a recalculation and not a repeat.
The heaviest date on the calendar, and four separate obligations land on it at once.
The statutory date is 31 January. In 2027 that falls on a Sunday, so everything above moves to Monday the 1st. Treat that as a weekend of grace, not two extra working days.
Form 1099-MISC runs on a different clock, which catches people out. Recipient copies are due by 1 February, but the IRS copy isn't due until 1 March on paper, or 31 March if you file electronically.
Partnership and S-corporation returns. Form 1065 and Form 1120-S, together with the K-1s that go to each partner or shareholder.
The K-1 is the part that matters to everyone else. Your partners can't file their own returns until they have it, so a late entity return doesn't just cost you — it holds up everybody attached to the business.
Extending moves this to 15 September 2027.
One easily missed item shares this date. If you want S-corporation treatment for the 2027 tax year, Form 2553 is due 15 March 2027. Miss it and you're waiting a full year, which is an expensive way to learn about a filing deadline.
Individual and C-corporation returns. Form 1040 and Form 1120. First-quarter 2027 estimated tax is due the same day, which is its own small trap — you're paying forward into the new year at the same moment you're settling up on the old one.
Extending moves the return to 15 October 2027.
Worth saying plainly, because it's the single most expensive misunderstanding in this whole article: an extension to file is not an extension to pay. The return can wait. The money cannot. If you extend without paying what you owe, interest and penalties run from April regardless of how neat the paperwork is.
In twenty years I have watched very few businesses miss a date because they didn't know it was coming. They miss it because the books weren't in a state to produce the numbers, and the fortnight that should have been review turned into reconstruction.
Every date above is really a deadline for something that happens earlier: the W-9 collected in October, the vendor payments coded consistently all year, the estimated payment recalculated in November rather than assumed in January. Do that part and these dates are administrative. Skip it and they're a scramble, every year, forever.
Federal dates above are drawn from the IRS tax calendar for 2027 (Publication 509), which was still an early-release draft when this was written in November 2026. Dates occasionally shift. This is general information about filing deadlines, not tax advice for your situation — your CPA or tax preparer should confirm what applies to you before you act on it.
That's a fixable problem, and it's much cheaper to fix in November than in February. Fifteen minutes on the phone, no cost, no obligation — I'll tell you honestly what shape your file is in and what it would take to be ready.
Regina · RMD Premium Bookkeeping · QuickBooks Online Level 2 Certified · QuickBooks Online Payroll Certified