On the morning of January 2, a lot of freelancers do the same quiet thing. They open their banking app, scroll back through twelve months of deposits, and feel their stomach drop a little. They aren't looking at a mistake. They're looking at a year that is finished. Whatever the tax bill is, it has already been written. The only thing left is to find out how big it is.

The cruel part is that the same bill, viewed on November 12, was still negotiable. The facts of your year were mostly set by then, but several of the choices that shape the final number were still open. They close on December 31. Most people never look at the number until the window has shut.

This piece is about the look you take in November: a short projection that turns the vague dread of "I probably owe something" into a figure you can act on.

Why November is the useful month

Tax law mostly asks one question: what happened in this calendar year? If you're a typical freelancer on the cash method, income counts when you receive it and expenses count when you pay them. That means the year's shape is decided by dates, and some of those dates are still ahead of you in November.

By mid-November you know roughly 85 to 90 percent of your year. You know what you've billed, what's still outstanding, and what you've spent. You also still have about seven weeks to change what you pay, buy, and contribute before the books close.

In January you know everything and can change almost nothing. In June you can change everything and know almost nothing. November is the narrow stretch where both are partly true.

The four-number projection

You don't need software or a spreadsheet with tabs. You need four numbers on a single page.

1. Net profit so far. Take the income you've actually received this year and subtract the business expenses you've actually paid. Pull this from your bookkeeping, not from memory. Memory is generous with expenses and forgetful about income.

2. Net profit for the rest of the year. Estimate what you'll still collect before December 31, based on invoices that are realistically going to be paid, minus expenses you know are coming. Be conservative on income and honest on expenses. Add it to the first number, and you have a full-year profit estimate.

3. Your tax on that profit. Two layers apply. Self-employment tax is 15.3% (12.4% Social Security plus 2.9% Medicare) applied to 92.35% of your net profit, subject to the Social Security wage base. Then federal income tax applies to your taxable income, which is your profit minus half your self-employment tax, minus the standard deduction or your itemized deductions, minus the qualified business income deduction if you qualify. If your household has other income, such as a spouse's paycheck, include it. Add your state's tax on top. A rough but honest version of this is fine; the goal is accuracy within a few hundred dollars, not a filed return.

4. What you've already paid. Add up the estimated payments you've made this year, plus any income tax withheld from a W-2 job. Subtract that from number three.

The result is the gap: what you'll owe if nothing changes.

Read the gap against two thresholds

The gap alone doesn't tell you whether you're in trouble. Two comparisons do.

First, the safe harbor. In general, you avoid the underpayment penalty if your total payments for the year reach 90% of this year's tax, or 100% of last year's total tax (110% if last year's adjusted gross income was above $150,000). Check your prior-year return for that second figure. If your payments so far already clear it, a large gap is a cash-flow problem for April, not a penalty problem.

Second, the timing of the penalty. The IRS charges interest on underpayments quarter by quarter, so the penalty depends on when money arrived, not only how much. A last-minute payment in January helps your balance but doesn't erase a thin third quarter. You can still reduce your exposure, though, and it helps to know the penalty is really interest rather than a fine.

If you're short on both measures, you have a decision. If you're safe on at least one, you can relax about penalties and focus on the size of the final bill.

Which levers close on December 31, and which don't

This is the part people get backwards. Some moves expire at year-end. Others stay open until you file. Sorting them tells you what's urgent.

Expiring December 31:

  • Business purchases. Equipment must be bought and placed in service by year-end to count for this year. A laptop in a box on December 30 is not the same as a laptop in use.
  • Expense payments. Under the cash method, a charge on a credit card in December counts in December, even if you pay the card bill in January.
  • Opening a solo 401(k). The plan generally needs to exist by year-end for the employee-deferral side to be available for this year. This is worth confirming with your plan provider, because the rules for deferrals and employer contributions differ.
  • Income timing. Whether a December invoice is paid in December or January can move income across the line. The constructive-receipt rule means you can't simply refuse to pick up a check that's available to you, so this is a lever for how you invoice, not for hiding money.

Open until you file:

  • IRA and HSA contributions for the year can generally be made up to the filing deadline in April.
  • SEP-IRA contributions can generally be made up to the filing deadline, including extensions.

The practical rule: do the expiring things first, even if the later ones feel bigger.

The trap of the tax-driven purchase

A projection can tempt you into spending. Resist it unless you were going to buy the thing anyway. A deduction reduces your tax by your marginal rate, not by 100%. A $2,000 purchase that you didn't need costs you $2,000 and saves you perhaps $500 to $700 once income tax and self-employment tax are counted. You still end up behind. Use the projection to time purchases you were already planning, not to invent new ones.

Your next moves

  • Block 45 minutes this week and build the four-number projection. Write the numbers on one page: profit so far, profit expected for the rest of the year, estimated tax, and payments already made.
  • Find last year's total tax on your 2025 return (Form 1040, the "total tax" line) and compare your payments to date against 100% of it, or 110% if your income was above $150,000. This tells you immediately whether the penalty is even in play.
  • Decide on any planned equipment purchase now. If you were going to buy a laptop, camera, or desk anyway, buy it and start using it before December 31, and keep the receipt with a one-line note about its business purpose.
  • Call or log in to a retirement account provider this month to ask whether you can open a solo 401(k) before year-end, and what the deadline for setting up deferrals is. Even if you only decide in April how much to put in, the account may need to exist by December 31.
  • Put January 15 in your calendar as the date for your final estimated payment, and set aside whatever the projection says you'll owe in a separate savings account today, rather than in April.

The calm that comes from a number

Most tax anxiety isn't about the money. It's about not knowing, and the shape that unknown takes in your head is always worse than the figure on the page. A projection won't make the bill smaller by itself, but it converts a feeling into a task, and tasks can be finished.

Payday is built around that same habit. It connects to Stripe or your bank, tracks your running profit, calculates each quarter's estimated payment, nudges you before the deadline, and exports a TurboTax-ready file when the year is done, so a November projection is something that's already sitting there rather than something you have to assemble. If you'd rather not meet your tax bill for the first time on January 2, you can see how it works at payday.lumenlabs.works.