FIRE to IRIS migration guide: what 1099 filers must do before the 2027 season

The dates

What is changing

FIRE (Filing Information Returns Electronically) accepted fixed-width text files in the Publication 1220 format and returned results days later. IRIS (Information Returns Intake System) is the replacement the IRS has run alongside it since 2023. It takes XML through an API or CSV uploads through a web portal, validates each return as it is submitted, and reports one of three outcomes for a submission: accepted, accepted with errors, or rejected. Beginning with the 2027 filing season, every form FIRE accepted is filed through IRIS: the 1099 series (including 1099-NEC, MISC, K, INT, DIV, B, DA and R), 1042-S, the 1098 series, W-2G, 3921, 3922 and the 5498 series. Form W-2 is unaffected; it goes to the Social Security Administration as before.

Nothing about the underlying rules changes. Thresholds, due dates, the penalty tiers and the TIN rules are the same; what changes is the pipe, and the fact that a missing or malformed field now stops the return at the door instead of surfacing on a notice months later.

The file format changes with it. Publication 1220, the FIRE specification, becomes obsolete when FIRE retires. What it covered moves to the IRIS schema package and three publications: 5717 (the Taxpayer Portal user guide), 5718 (the A2A electronic filing specifications) and 5719 (the test package).

IRIS is not new or lightly used. The new broker form, 1099-DA, accounts for most of the 2026 volume, but the familiar forms are there too: over 26 million 1099-B, 24 million 1099-NEC, 21 million 1099-INT and 12 million 1099-MISC records went through IRIS in the 2026 season, before FIRE was switched off.

Who has to act

Getting an IRIS TCC

1. Decide which TCC you need. A Taxpayer Portal TCC lets you key or upload returns on the IRS website. An A2A (application-to-application) TCC is for software that transmits XML directly. A company that only files its own returns needs the portal TCC; a company transmitting for others, or integrating its own system, needs A2A.
2. Sign in to the IRS e-Services application with an ID.me-verified account. Every responsible official and contact on the application needs their own verified identity.
3. Complete the IRIS Application for TCC. Legal name and EIN (an SSN or ITIN is not accepted as the firm identifier), the role (issuer, for your own returns only, or transmitter, for your own and others), the forms you will file, the transmission method, and the people: at least two Responsible Officials and two Contacts, or one of each for a sole proprietorship, S corporation or single-member LLC. Each Responsible Official signs the application with the five-digit PIN they created at sign-in; the application is not processed until every one of them has signed (Publication 5903).
4. Wait for the code. The IRS says to allow up to 45 days. The TCC appears on your application summary as soon as it is assigned and can be used immediately; the approval letter follows by mail. A portal TCC is five characters beginning with D. If the application sits in Submitted Pending Review for more than 45 days, call the help desk (Publication 5717, section 2.2.2).
5. For A2A only: obtain an API Client ID, download the schema package, and pass IRIS Assurance Testing before production.

Taxpayer Portal or A2A?

The portal walkthrough goes screen by screen, the A2A developer guide covers the Client ID, tokens, endpoints and ATS testing on the software side, and the IRIS CSV upload checker tests a template file for the rejection causes before you upload it. Firms filing for clients have their own page: IRIS for accountants.

What works differently in IRIS

• Validation happens at submission. A TIN that is not nine digits, a name over the field length, or a missing required box is rejected immediately. Run a format check on the file before you upload it.
• “Accepted with errors” is a real status. The return is filed but flagged; you correct it, and the correction clock for penalty purposes is the one on the figures page.
• Corrections use the same system. Type 1 and Type 2 corrections, covered in the corrections guide, are filed through the portal or the API rather than through a separate FIRE upload.
• Name and TIN rules are enforced as written. IRIS validates name-line length and characters; a name that FIRE tolerated can fail. The name control rules explain what the IRS is deriving from that line.
• One correction per original. IRIS links a correction to the original record by its unique record ID and lets you correct an original once; a second fix is filed against the most recent accepted correction, not the original. Issuer name or TIN errors cannot be corrected in IRIS at all; those go by letter to the IRS at Kearneysville, as the corrections guide explains.
• Rejections have a 60-day replacement window. A rejected transmission or submission that is replaced within 60 days keeps the original filing date; after 60 days it is treated as filed on the replacement date, which is what the late-filing penalty is computed from. Wait for the Rejected or Partially Accepted status before replacing.
• Combined Federal/State Filing continues for participating states; check the state requirements page for the ones that still require direct filing. In the portal you can report payments and withholding for up to two states per return; A2A takes as many as needed. The CF/SF in IRIS page has the consent step, the eleven forms and the state list.
• Correcting a return first filed through FIRE. From January 1, 2027 that correction is filed in IRIS too, including for prior years. In the A2A XML, the correction points back to the FIRE original with two new fields: one marks the original as filed through another system, the other names that system (FIRE). Publication 5718 and the tax year 2026 schema carry the detail; if a service or software files for you, ask whether it handles them. If your software still writes Publication 1220 files, the free Pub 1220 to IRIS converter on tincomply.com turns them into IRIS XML and portal CSV files, keeps corrections of FIRE-filed returns in their own transmission, and lists what it could not carry across.
• The A2A schema version number is 5.0.7. The tax year 2026 schema (v1.2, released September 24, 2026) fixes SchemaVersionNum at 5.0.7 in the transmission manifest. The IRS known-issues entry of October 13, 2026 says that from October 7, 2026 IRIS A2A transmissions for tax years 2026 and 2025 in the Assurance Testing System (ATS) must use 5.0.7, and under a prior-years heading tells filers of tax years 2022 to 2024 to use 5.0.7 as well; the entry names the ATS environment, so check the IRS known issues page before sending prior-year originals or corrections. The tax year 2026 schema and rules changes page has the entry and the rest of the package diff. The portal's CSV upload is not affected. The free IRIS 1099 File Checker on tincomply.com flags a missing or outdated version before you send.
• The portal has no test environment. The IRS says the Taxpayer Portal “only accepts live production data.” Anything you submit there is filed. Testing exists only for A2A, in the Assurance Testing System (ATS), where the tax year 2026 test year opened in October 2026. ATS is for testing software, not for checking a real file: it “performs schema and business rules validation,” and “IRS downstream systems will not process test submissions.” It also refuses real data. “Taxpayer live data must not be submitted in IRIS ATS. The IRIS ATS environment is not a secure environment and testing of live TINs will result in a rejection”; issuer and recipient TINs in a test file must begin with three zeros (Publication 5719, Rev. 10-2026, sections 2 and 6.1.1). To check a real portal file before submitting, use the IRIS CSV upload checker, which runs in your browser and uploads nothing.
• The layout is boxes and elements, not positions. A Pub 1220 file is fixed-width: box 1 of a 1099-NEC is amount code 1 in positions 55-66 of the B record. In IRIS the same box is the element NonemployeeCompensationAmt in the form's XML record, or the column "Box 1 - Nonemployee Compensation" in the portal CSV template, and the payer block moves out of the record into a submission header. The Pub 1220 to IRIS crosswalk lists every position and where it lands, the position lookup answers one field at a time, and each form page shows the IRS form with the IRIS element at every box and the CSV template columns with a sample file.
• Paper forms split the address, electronic files do not. Forms revised in 2026 break the address into separate boxes on paper. The electronic file keeps two address lines, city, state and ZIP, with no separate suite or apartment field; where the paper form and the electronic specification differ, the IRS says the specification governs.

Forms arriving in IRIS for the 2027 season

Publication 5717 (Rev. 9-2026) lists eight additions for tax year 2026. Three are new forms: 1098-VLI, 1099-LPS and 5498-TA. Three are long-standing FIRE forms moving over: Form 8027 (tip income), Form 8596 (federal contracts) and Form 8955-SSA (separated participants with deferred vested benefits), so a filer of any of those needs an IRIS TCC like everyone else. And two are requests that used to be separate: Form 8809, the extension of time to file, and Form 15397, the extension of time to furnish recipient statements, are both filed inside IRIS. The IRS has also opened a Foreign Filer TCC Registration System for filers outside the United States whose responsible officials cannot complete the identity verification an ordinary TCC requires.

A four-week plan

What the IRS manual says about FIRE, TCCs and files

IRM 3.42.9IRM 3.42.9Internal Revenue Manual, irs.gov (rev. Dec. 5, 2025) is the manual for the help desk behind FIRE and IRIS. Points a filer should know:

• FIRE retirement: "Tax Year 2026/Filing Season 2027 is the targeted date for the retirement of the FIRE System."
• The 10-day window (FIRE only). A file in "Good" status is released to processing after 10 calendar days. Inside that window you can ask the help desk to mark it Bad and send a replacement, which is not a correction and does not feed the penalty system. After the window, a corrected file is required. A Bad file must be replaced within 60 days; the IRS expects you to check status within five business days. IRIS has no hold on accepted files; there the acknowledgment status decides between replacement and correction (see 1099 corrections).
• TCC hygiene. Two Responsible Officials are mandatory for most entities, every person on the application is validated against SSA records continuously and screened against the OFAC list quarterly, a deceased official must be replaced within 30 days, a TCC unused for two years goes inactive and is then dropped, and a new FIRE TCC takes up to 48 hours to work (an IRIS TCC works immediately). One TCC per EIN can transmit for any number of companies, but the FIRE login must use the EIN the TCC was issued to.
• Extensions and waivers. No approval letters are issued for Form 8809; keep the acknowledgment. A FIRE TCC is now required even for the fill-in 8809. Form 8508 waivers are granted for only eight listed reasons, and an extension can silently fail to post if the payer name control does not match IRS records.
• Duplicates are hunted. A weekly job flags files from the same TCC with record counts within five of each other; expect a call rather than silent de-duplication.

Full detail, with subsection citations: how extensions and e-file waivers are checked in the penalty process.

Public guidance treats FIRE and IRIS as interchangeable ways to file. Inside the IRS they are not the same tag. The IRPTR manual's payer-level screens carry a per-document SOURCE CODE that reads "ELECTRONIC" for codes 'C' or 'T', "PAPER" for 'G' or 'P', and on the 1099 screens (K, NEC, G, DIV, INT, MISC, OID, PATR and R) also "IRMOD A2A" for 'A' or 'B', "IRMOD 1099 Portal" for 'M' or 'N' and "IRMOD SCRIPS" for 'K' or 'L' (IRM 2.3.35IRM 2.3.35Internal Revenue Manual, irs.gov, Figures 2.3.35-6 and 2.3.35-12 to 2.3.35-19, Dec. 4, 2014; Jan. 20, 2026 transmittal). "IRMOD" is the manual's name for the IRIS channels: application-to-application, the Taxpayer Portal, and scanned paper. The manual never uses the word IRIS, and it does not say what distinguishes the two letters within each pair, so do not read them as original versus corrected. The same payer summary screen, IRPTRI, shows TOTAL NUMBER OF ELECTRONIC FILED DOCUMENTS beside TOTAL NUMBER OF PAPER FILED DOCUMENTS for a payer TIN (IRM 2.3.35.10.5(4))IRM 2.3.35.10.5(4)Internal Revenue Manual, revised Dec. 4, 2014, irs.gov; the manual does not say the split is used for e-file mandate enforcement, only that it is displayed. What an employee sees for a single return is in what the IRS sees when it pulls up your 1099.

Questions people ask

🎮 Test yourself: FIRE to IRIS: The Move, a 2-minute knowledge game.