Guide
Year-end tax: gather the records and check the dates before December 31
The last weeks of the year are the easiest time to fix tax paperwork, and some doors close with the year. This guide is a checklist for that window: which records to collect, which items close on December 31, and which run into the new year. It does not compute your tax, and it does not tell you what to contribute, convert or give. It helps you arrive at filing season with complete records and the right questions.
Key takeaways
- Gather income records early. The IRS has a set route when a W-2 or 1099-R is missing or wrong.
- Some items close with the year: the annual 401(k) deferral, required minimum distributions, charitable gifts and Roth conversions all count by date.
- Some items run past December 31: IRA and HSA contributions run to the April filing deadline, and the fourth estimated payment is due in mid-January.
This guide is for US readers. It is educational, not individual tax, investment or legal advice. Valora is not a registered investment adviser and is not arranging advisor matches or introductions at this time. It covers federal rules only, not state or local deadlines. Dollar limits are quoted from live IRS pages as of the dates in Sources, and every deadline keeps its conditions.
First, gather the records
The IRS get-ready guidance tells taxpayers to gather and organize tax records before filing and to wait to file until the records are in hand. Year-end is the time to see what is still missing, while payers can still fix it.
Collect a Form W-2 from each employer, a Form 1099 for each other income source (bank, broker, client, marketplace, retirement payer), and a Schedule K-1 for each partnership or S corporation you have an interest in. For each one, write down who issues it and when it arrived last year. If a K-1 usually arrives late, note it now so it does not surprise you in March.
If a W-2 or Form 1099-R has not arrived by early February, or the information on it is wrong, the IRS says to contact the employer or payer first. If the form is still missing or uncorrected by the end of February, you may call the IRS, which contacts the payer and sends you Form 4852 as a substitute. You can file using Form 4852 with your best estimates if the form does not arrive in time, and if the real form later shows different numbers, you file an amended return on Form 1040-X (IRS Topic 154).
Collect a Form 1099-B from each broker you sold investments through. The IRS says brokers file it to report sale proceeds (About Form 1099-B, reviewed October 2, 2026). For trades made in the last days of December, ask your broker whether the form uses the trade date or the settlement date, so a late-year sale lands in the tax year you expect.
Closes on December 31
401(k) deferrals
The IRS limits elective deferrals per year. For 2026, the limit is $24,500, with a catch-up of $8,000 for those 50 and over, and $11,250 for those aged 60 to 63 under a SECURE 2.0 change (IRS COLA table, last reviewed August 24, 2026). Deferrals come out of each paycheck, so the last pay date of the year is the practical close. If you want to change your deferral for this year, ask your plan now whether it can still count.
Required minimum distributions
If you are already required to take RMDs, the IRS says each year's distribution must be withdrawn by December 31. If this is your first RMD year, the IRS allows the first distribution as late as April 1 of the following year, but the second is then due by December 31 of that same year, which stacks two taxable distributions into one tax year (IRS RMD topic page, last reviewed April 8, 2026). Check whether an RMD applies to you this year and whether it is already taken. The RMD estimate calculator can estimate an amount from a balance and an age; the deadline question above is the one to settle first.
Charitable gifts
The IRS says a donation you want to deduct for a tax year must be made by December 31 of that year (IRS Tax Tip 2022-191, December 15, 2022). Its year-end guidance adds the timing mechanics: a gift charged to a credit card counts when charged, and a check counts when mailed by the last day of the year (IRS Get Ready for Taxes, December 16, 2019).
Keep the records as you give. For every cash gift of any amount, the IRS requires a bank record or a written communication from the organization showing its name, the amount and the date. For any gift of $250 or more, you also need a contemporaneous written acknowledgment from the organization that says whether it provided any goods or services in exchange. For noncash gifts over $500, Form 8283 goes with the return (IRS Topic 506, last reviewed September 24, 2026). The year-end question: do you already have the acknowledgment for each gift of $250 or more, or do you need to request it now?
Roth conversions
One date fact only: a Roth conversion is reported for the tax year it happens in. The Form 8606 instructions handle each year's conversions in that year's part of the form, so a conversion made by December 31 counts for that year (Instructions for Form 8606, 2025 edition). Whether to convert, and how much, is a bracket and household question for your tax professional. The Roth conversion tax cost calculator illustrates a flat-rate estimate and states its own limits.
Runs into the new year
IRA contributions
IRS Publication 590-A says contributions for a year can be made at any time during the year or by the due date for filing the return for that year, not including extensions (2025 edition; its example gives April 15, 2026 for 2025 contributions). For 2026, the IRA limit is $7,500, with a $1,100 catch-up for those 50 and over (IRS COLA table). One record habit matters here: if you contribute between January 1 and the April deadline, tell the sponsor which year the contribution is for, because otherwise the sponsor can assume and report it for the current year (Publication 590-A).
HSA contributions
IRS Publication 969 says HSA contributions for a year can be made through the April filing deadline, and that an employer contribution made early in the year can be allocated to the prior year if it is designated as such (2025 edition; its example gives April 15, 2026 for 2025). Contributions are reported on Form 8889 with the return. If you mean to top up for this year, note the designation question now rather than in April.
FSA balances
A flexible spending arrangement runs on your employer's plan terms, not on the federal tax calendar. Publication 969 describes grace periods and carryovers as features a plan may offer (the 2025 carryover cap it cites is $660). The year-end question is for your plan document or benefits office: must the balance be spent by December 31, is there a grace period, and how much, if anything, carries over?
The fourth estimated payment
The IRS estimated-tax FAQ (last reviewed October 16, 2026) divides the year into four payment periods, and the period from September 1 to December 31 is due January 15 of the following year, moving to the next business day if the date falls on a weekend or holiday. The IRS estimated-taxes page (last reviewed September 25, 2026) says individuals generally must pay if they expect to owe $1,000 or more, and describes conditions that avoid the underpayment penalty: owing less than $1,000 after withholding and credits, or having paid at least 90% of the current year's tax or 100% of the prior year's, whichever is smaller. Whether those conditions cover your year is a question for your tax professional. This page does not compute them.
The checklist
Two short lists, plus a question for each line. Print or copy them.
List 1, records to collect. Each W-2. Each 1099: bank, broker, client, marketplace, retirement payer. Each Schedule K-1. Each Form 1099-B. Charitable acknowledgments for gifts of $250 or more, and bank records for smaller gifts. HSA and FSA year-end statements. A list of estimated payments made this year, with dates. For each line: who issues it, is it here yet, and who can fix it if it is wrong?
List 2, dates to check. December 31: 401(k) deferral room, this year's RMD, charitable gifts, any Roth conversion. January 15: the fourth estimated payment. April filing deadline: IRA and HSA contributions, with the designate-the-year reminder. FSA plan dates: from your plan document.
A fictional example. Theo has a W-2 job and does freelance work on weekends. His record list has a W-2, a 1099-NEC from each of two clients, and a 1099-INT from his bank. In January he notices one client's 1099-NEC is missing, so he asks the client for it; if it has not arrived by the end of February, he knows from Topic 154 that he can call the IRS. His date list has the fourth estimated payment due January 15 and an IRA contribution he plans to make in March, designated for the prior year. Theo is invented and no numbers are computed; the point is that every line has an owner and a date.
Where this page stops
This page does not compute your tax, estimate your refund, or work out any safe-harbor amount. It does not cover state or local deadlines, business or payroll filings, or the taxation of any specific investment. It does not tell you whether to contribute, convert, sell or give; those are decisions for you and your tax professional. Trade-date, settlement and basis questions belong to your broker. For the ongoing strategy side, reviewed during the year with a professional, see the tax-planning guide; this page is only the year-end checklist.
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Common questions
What if a W-2 or 1099 has not arrived by February?
Contact the employer or payer first. If the form is still missing or wrong by the end of February, you may call the IRS, which contacts the payer and sends Form 4852 as a substitute. You can file with Form 4852 using estimates, and amend later with Form 1040-X if the real form differs (Topic 154).
Does the December 31 deadline apply to my IRA too?
No. IRA contributions for a year run to the April filing deadline, not including extensions (Publication 590-A). It is 401(k) deferrals that close with the year, because they come out of each paycheck.
I gave to charity in December. What records do I need?
For any cash gift, a bank record or a written communication from the organization with its name, the amount and the date. For any gift of $250 or more, also a contemporaneous written acknowledgment saying whether you received goods or services in exchange (Topic 506).
What is the January deadline people miss?
The fourth estimated payment for the September 1 to December 31 period, due January 15 of the following year (IRS estimated-tax FAQ). If you had income without withholding this year, ask your tax professional whether it applies to you.
What should I send through the inquiry form?
Your question in a sentence or two, which records you already have, and which date you are unsure about. Do not send tax documents, account numbers or Social Security numbers. Valora replies by email with next steps and does not arrange advisor matches.
Sources
Internal Revenue Service: COLA increases for dollar limitations (last reviewed August 24, 2026); Retirement topics: Required minimum distributions (last reviewed April 8, 2026); Estimated taxes (last reviewed September 25, 2026); Estimated tax FAQ (last reviewed October 16, 2026); Topic 154, Form W-2 and Form 1099-R (date not shown, accessed October 19, 2026); About Form 1099-B (last reviewed October 2, 2026); Topic 506, Charitable contributions (last reviewed September 24, 2026); Publication 590-A (2025); Publication 969 (2025); Instructions for Form 8606 (2025); Get ready to file your taxes (date not shown, accessed October 19, 2026).
IRS newsroom: Tax Tip 2022-191 (December 15, 2022); Get Ready for Taxes: what to do before the tax year ends (December 16, 2019). Both are older pages used only for the gift-year date and card and check timing mechanics.
Valora pages, as published and read October 19, 2026: tax-planning guide, RMD estimate calculator, Roth conversion tax cost calculator.