IRIS Filing Guide for CPAs and Accounting Firms

What the FIRE to IRIS Transition Means for Accounting Practices

As a CPA or accounting professional, you've likely filed 1099 information returns through the FIRE system for years — possibly decades. The FIRE system's fixed-width Publication 1220 format became second nature: generate the file from your tax software, upload to FIRE, download the acknowledgment, and move on.

That workflow ends after December 31, 2026. The IRS's replacement, IRIS (Information Returns Intake System), uses a fundamentally different approach. Instead of fixed-width flat files, IRIS accepts XML-formatted data. Instead of a single bulk upload portal, IRIS offers both a Taxpayer Portal for manual entry and an Application-to-Application (A2A) channel for automated submissions.

For accounting firms managing filings across dozens or hundreds of clients, each with different form types and payer information, this transition requires careful planning. The good news: the underlying obligations haven't changed. The same forms, the same deadlines, the same penalties. Only the plumbing is different.

What Changes for CPAs Under IRIS

Transmitter Control Code (TCC)

Under FIRE, your firm likely held a TCC that authorized you to transmit information returns electronically. IRIS requires a separate IRIS TCC, which you must apply for through the IRS's IR Application for TCC system. The application process can take 45 days or longer, and the IRS requires a background check and suitability review for responsible officials.

If your firm files for clients as a transmitter, you need an IRIS TCC with the appropriate role — either as a Transmitter (filing on behalf of others) or an Issuer (filing your own firm's 1099s). The TCC application process is more involved than it was under FIRE, with stricter vetting requirements.

File Format: Fixed-Width to XML

The most significant technical change is the file format. FIRE used Publication 1220's fixed-width record layout with T (Transmitter), A (Payer), B (Payee), C (End of Payer), and F (End of Transmission) records. IRIS uses XML schemas that follow different structural conventions entirely.

For firms using professional tax software that handles the file generation, this change may be transparent — your vendor will update their export format. But for firms that use custom tools, spreadsheets, or in-house scripts to generate FIRE files, this is a substantial rewrite. See our guide to converting FIRE files to IRIS XML for technical details.

Submission Process

FIRE was straightforward: log in, upload your file, wait for acknowledgment. IRIS works differently depending on which channel you use:

• IRIS Taxpayer Portal: A web-based interface at IRS.gov where you can key-enter individual 1099s or upload CSV files. Suitable for small volumes but impractical for firms with hundreds of clients.
• IRIS A2A (Application-to-Application): An API-based channel for bulk XML submissions. Requires a TCC, technical integration, and XML schema compliance. This is the enterprise path, analogous to how FIRE handled large volumes.

For most accounting firms, neither option is ideal on its own. The Taxpayer Portal is too manual for multi-client practices, and the A2A channel requires technical resources most accounting firms don't have in-house.

What Doesn't Change Under IRIS

Despite the infrastructure changes, the regulatory framework remains identical:

• Filing deadlines: 1099-NEC is still due January 31. 1099-MISC, 1099-INT, 1099-DIV, and other forms are still due by their established dates (typically March 31 for electronic filing).
• Penalty structure: Penalties for late or incorrect filings remain unchanged — $60 to $630 per form depending on lateness and intent. The penalty caps and reasonable cause exceptions apply the same way.
• Client obligations: Your clients are still responsible for the accuracy of payer and payee data. The transition to IRIS doesn't shift liability or change who is considered the filer of record.
• Correction process: You can still file corrected returns. IRIS has its own correction mechanism, but the concept of Type 1 and Type 2 corrections carries forward.
• Recipient copies: IRIS only handles the IRS copy. You still need to furnish recipient copies (Copy B) to payees by the applicable deadline, whether by mail or electronically with consent.

Multi-Client Filing Considerations for Accounting Firms

The biggest operational challenge for CPAs is managing multiple clients through a single filing workflow. Under FIRE, you could include multiple payers in a single transmission file — one T record at the top, multiple A/B/C blocks for each client, and an F record at the end. Your software generated one file; you uploaded it once.

IRIS handles multi-payer submissions differently. The Taxpayer Portal requires you to work with one payer at a time. The A2A channel supports batch submissions, but each submission is tied to a specific TCC and transmitter relationship. If you manage 50 clients and each has a mix of 1099-NEC, 1099-MISC, and 1099-INT filings, you need a workflow that efficiently handles all of them without requiring 50 separate login sessions.

Common Scenarios for Accounting Firms

Scenario	Form Types	IRIS Challenge
Small business clients	1099-NEC for contractors	Manual portal entry feasible but time-consuming across many clients
Property management clients	1099-MISC for rent payments	Volume per client may be low, but aggregate across clients adds up
Investment/trust clients	1099-DIV, 1099-INT, 1099-R	Multiple form types per client, complex data requirements
Construction/professional services	1099-NEC (high volume)	Clients with 50-500+ subcontractors need bulk submission
Medical/legal practices	1099-NEC, 1099-MISC	Regulatory sensitivity; accuracy and audit trail critical

IRIS Taxpayer Portal vs. A2A: Which Path for Your Firm?

IRIS Taxpayer Portal

The IRIS Taxpayer Portal is a free, web-based tool on IRS.gov. It allows you to:

• Key-enter individual 1099 forms one at a time
• Upload data via CSV templates provided by the IRS
• File up to 100 forms per submission
• View submission status and download acknowledgments

For accounting firms, the portal has significant limitations. There's no efficient way to manage multiple clients in a single session. The CSV upload has a 100-form limit per file. There's no API integration with your existing tax preparation software. And there's no bulk correction capability — you'd need to correct forms one at a time.

IRIS A2A (Application-to-Application)

The A2A channel is designed for high-volume, automated filing. It supports XML-based submissions through SOAP web services. However, it requires:

• An approved IRIS TCC with Transmitter role
• Technical staff capable of building and maintaining XML generation and SOAP integration
• Testing and certification with the IRS before going live
• Ongoing maintenance as the IRS updates schemas

Most accounting firms don't have in-house developers, making the A2A channel impractical as a direct integration. This is where third-party platforms bridge the gap.

Why CPAs Choose BoomTax for IRIS Filing

BoomTax eliminates the complexity of the IRIS transition for accounting practices. Instead of choosing between manual portal entry and building an A2A integration, BoomTax gives you a single platform that handles everything:

• All clients, one account: File for every client from a single BoomTax account. No per-client TCC applications, no switching between payer accounts.
• All form types: 1099-NEC, 1099-MISC, 1099-INT, 1099-DIV, 1099-R, and more — all supported through the same interface.
• No TCC needed: BoomTax holds the IRIS TCC and transmitter authorization. Your firm doesn't need to apply for or maintain its own TCC.
• FIRE file compatibility: If your software still generates Publication 1220 files, upload them directly to BoomTax. We convert to IRIS XML automatically — no format changes required.
• Bulk upload options: Import data from CSV, Excel, or FIRE-format files. No 100-form limits, no manual re-keying.
• Built-in validation: BoomTax validates TINs, amounts, and required fields before submission. Catch errors before they become IRS rejections.
• Recipient copy delivery: BoomTax can print and mail recipient copies or deliver them electronically, saving your firm the separate step of fulfilling Copy B obligations.
• Corrections handling: File corrected returns through the same interface. No need to navigate IRIS correction workflows directly.

Timeline: What CPAs Should Do Before December 31, 2026

The FIRE system shuts down on December 31, 2026. Here's a recommended timeline for accounting firms:

IRIS vs. Using a Third-Party Platform Like BoomTax

Capability	IRIS Taxpayer Portal	IRIS A2A (Direct)	BoomTax
TCC required	No (for manual entry)	Yes (45+ day application)	No — BoomTax handles it
Multi-client support	Manual switching	Batch capable	All clients in one account
File format	CSV (IRS template)	IRIS XML	CSV, Excel, FIRE-format, or manual entry
Volume limit	100 forms per upload	No limit	No limit
Recipient copies	Not included	Not included	Print, mail, or e-deliver
Technical expertise needed	Low	High (XML/SOAP)	None
Corrections	One at a time	Batch capable	Batch or individual

For a deeper comparison between the two IRS systems, see our IRIS vs FIRE comparison guide. For a broader look at filing platforms, see our roundup of the best IRIS filing software.

Frequently Asked Questions

For industry-specific guidance, see our IRIS filing guides for payroll and HRIS companies and banks and financial institutions. For step-by-step migration instructions, read how to migrate from FIRE to IRIS.