Tax Forms Explained: Every Form in the January Mailbox and What It Reports

Every tax form that lands in your mailbox in early 2027 is the same report the IRS is getting from the same payer. An employer sends a W-2, a bank sends a 1099-INT, a broker sends a 1099-B, a mortgage servicer sends a 1098. For tax year 2026, almost all of them are due to you by February 1, 2027, broker forms by February 16, and IRA contribution forms not until June 1.

That is the short answer. The longer one, below, is which form comes from which kind of account, the one or two boxes on each that end up on your return, the amounts below which no form is sent at all, and the three forms you do not need in hand to file.

What these forms are for

The IRS calls these documents information returns. A payer files one copy with the government and gives you another, which the instructions call the payee statement or Copy B.^[1] The point of the system is matching. The IRS compares the income and payments third parties report with what you put on your return, and when they disagree it sends a CP2000 notice proposing changes.^[17] The notice is not a bill, but it usually needs an answer.

So a form in your mailbox is less a request than a preview. Whatever it says, the IRS already has it, and the useful question is whether the figure agrees with your own records before you file.

The forms fall into three groups by what they do on a return.

The calendar for 2026 forms

The W-2 instructions for 2026 set the employee deadline directly: employers must furnish copies by February 1, 2027.^[2] For the 1099 family and Form 1098, the IRS table of due dates lists January 31 for most forms and February 15 for Form 1099-B (and for 1099-MISC when it reports attorney proceeds or certain other amounts).^[1] When a due date falls on a weekend or a legal holiday in the District of Columbia, the deadline becomes the next business day.^[1]

In 2027 that rule moves both dates. January 31 is a Sunday, so most 1099s and 1098s are on time if sent by Monday, February 1. February 15 is Washington’s Birthday, a federal holiday, so broker 1099-Bs are due by Tuesday, February 16. Form 5498 has the latest deadline of all: statements of IRA contributions are due by May 31, while the year-end account value is due by January 31.^[1] May 31, 2027 is Memorial Day, which puts the contribution statement at June 1.

The practical consequence is for anyone with a taxable brokerage account. Brokers often send interest, dividends and sales as one consolidated statement,^[14] and the sales part of it is not due until February 16. Filing in the first week of February with a brokerage account means filing before the form that reports your sales was due.

The forms that report income

Each income form maps to one kind of account or relationship, which is what makes the mail predictable. The box numbers below are the ones named in each form’s IRS instructions.

Three of these deserve a closer read.

W-2, box 1. Box 1 is taxable wages, and the instructions tell employers to leave out elective deferrals such as your 401(k) contributions.^[2] Those show up separately in box 12 under code D.^[2] That is why box 1 is usually smaller than your salary, and why it can differ from the Social Security and Medicare wage boxes beside it; the walk from gross pay to take-home explains each deduction that moves it.

1099-DIV, box 1a against 1b. Box 1a is all ordinary dividends and box 1b is the portion that is qualified.^[5] The two are taxed differently, so a return that copies box 1a and skips 1b overpays.

1099-B, box 1e and box 5. Box 1e is the cost basis the broker has on file. For older positions the broker may check box 5 instead, marking a noncovered security, and in that case it does not have to fill in the basis at all.^[3] Box 12 is checked when the basis was reported to the IRS.^[3] An empty box 1e means the basis is yours to supply, which is one more reason purchase records have to outlive the sale.

Thresholds, and the income no form reports

The amounts in the last column are reporting thresholds for the payer. They say nothing about whether you owe tax. The IRS is explicit on this for interest: you must report all taxable interest on your return even if you do not receive a Form 1099-INT.^[14] It says the same about selling goods or services through payment apps: whether or not a Form 1099-K arrives, the income goes on the return.^[15]

Two thresholds changed for 2026. The 1099-NEC instructions say the minimum for reporting certain payments, including nonemployee pay, rose to $2,000 for tax years beginning after 2025, with inflation adjustments possible from 2027.^[6] And payment apps and online marketplaces now have to report only when your payments for the year exceed $20,000 and number more than 200.^[7] The IRS adds that you may still receive a 1099-K below those figures.^[15]

For a freelancer, that combination means fewer forms in the mailbox and the same income on the return. A client who paid you $1,800 in 2026 owes you no 1099-NEC, and a year of payments through an app that stays under $20,000 may produce no 1099-K. Your own records of what came in are the only complete list, which is what paying yourself a salary from a buffer account leaves you with as a side effect.

The forms you do not wait for

Three forms in the pile are records rather than inputs, and waiting for them only delays a return that could already be filed.

Form 5498. It reports contributions to traditional, Roth, SEP and SIMPLE IRAs, rollovers, conversions, and the account’s fair market value.^[1] Roth contributions appear in box 10 and the account value in box 5.^[10] You do not file it; you keep it, because it is the custodian’s confirmation that a contribution happened and for which year. If you are working through the order to fund a 401(k), IRA and HSA, the 5498 is the receipt for the IRA step.

Forms 1095-B and 1095-C. These report health coverage from insurers and large employers. The IRS says they are not required to file, that you should not wait for them, and that you should not attach them to the return.^[12] Employers also no longer have to send Form 1095-C automatically: posting a clear notice on their website that you can ask for one satisfies the requirement.^[11] Not getting one in the mail is normal.

Form 1095-A is the exception. If you bought coverage through a Health Insurance Marketplace, the 1095-A is what you use to complete Form 8962 and reconcile the premium tax credit, and the IRS says to wait for it before filing.^[13]

One household’s checklist

The easiest way to know a pile is complete is to build the list of expected forms from your accounts before the envelopes arrive. Take an illustrative household with a job, two bank accounts, a brokerage account, some freelance work, a mortgage and an IRA.

Six forms should arrive. Two pieces of income, the $7 of interest and client B’s $1,500, will never have a form and still belong on the return. The W-2 shows $63,000 in box 1 rather than $68,000, because the 401(k) deferral is excluded and reported under code D instead.^[2] The 1098 comes because the servicer received at least $600 of mortgage interest, the form’s threshold.^[9] The brokerage statement is the one to wait for, and the 5498 can arrive after the return is filed without changing it.

The list in the first column is the same list you would make to add up what you own and owe: every account that earned interest, paid a dividend, held a retirement contribution or charged mortgage interest sends a form. In LumaLedger, the linked accounts on the ledger are that list already, and the documents vault files each PDF as a tax document with its tax year, so in February the year’s folder is a filter rather than a drawer.

When a form is missing or wrong

1. 1
   Check the payer’s website first

   Banks and brokers usually post tax forms in the account’s online documents. If you chose electronic statements, that may be the only copy you get.
2. 2
   Ask the payer for it, or for a correction

   A form with the wrong amount or a missing box is corrected by the payer, who files the correction with the IRS as well. Your return should match the corrected form.
3. 3
   Call the IRS at the end of February

   If a W-2 or 1099-R has not arrived by the end of February, the IRS will contact the employer or payer for you and send you Form 4852.
4. 4
   File with Form 4852 if it still does not come

   Estimate the wages or payments and the tax withheld on Form 4852. If the real form later differs, file Form 1040-X.
5. 5
   Answer a CP2000 if one arrives

   If the IRS’s copy disagrees with your return, the notice proposes changes. Agree, or explain with records why the form is wrong.

The IRS process in steps three and four is spelled out in Topic 154: call 800-829-1040 if a missing or corrected W-2 or 1099-R has not come by the end of February, and use Form 4852 if it still is not there in time to file, amending with Form 1040-X if the real one differs.^[16] The CP2000 in step five is the system working as designed, and the IRS notes that the difference it finds may raise your tax, lower it, or leave it unchanged.^[17]

None of this is tax advice, and a year with a business, a large sale or an inherited account is worth a professional’s eye. For most households, though, the work is a list made in January and ticked off in February: every account, the form it owes you, the date it is due, and the income that comes with no form at all.