Tax Authorities Are Scaling AI; Financial Institutions Can’t Afford to Lag Behind

Across the globe, tax authorities are rapidly modernizing their enforcement techniques including embedding artificial intelligence into their core operations. The goal is to transform how tax returns are reviewed, disputes are resolved, and compliance risks are identified. What was once a largely manual, case‑by‑case process is being replaced by data‑driven systems that prioritize speed, consistency, and enforcement efficiency.

Looking at some countries with recent announcements, Japan, the United States, and Brazil each illustrate a different facet of this shift. Together, they signal a clear message to financial institutions: tax compliance is moving into an AI‑enabled, real‑time environment, and legacy, manual workflows are no longer sufficient.

Japan: AI‑Driven Audits and Risk Scoring at Scale

Japan’s National Tax Agency (NTA) has emerged as one of the most advanced adopters of AI in tax administration. Since at least fiscal year 2023, the NTA has integrated machine‑learning models into income tax audits, using historical filing data and prior audit outcomes to risk‑score taxpayers and identify potential underreporting.

These systems are no longer experimental. In recent reporting periods, AI‑assisted audits contributed to record levels of additional tax assessments, particularly among high‑net‑worth individuals and complex taxpayers. Japan’s broader digital transformation strategy explicitly emphasizes using AI and data analytics to make enforcement activities more efficient and advanced, while allocating human reviewers to the most complex cases.

For taxpayers and financial institutions alike, the implication is clear: patterns, inconsistencies, and missing data are increasingly detected algorithmically, and not through random selection.

United States: AI at the Core of IRS Enforcement and Review

In the United States, the Internal Revenue Service has significantly expanded its use of AI across enforcement, audit selection, and operational efficiency. As of mid‑2025, the Government Accountability Office says the IRS maintained over 120 active AI use cases, spanning return risk scoring, fraud detection, document classification, and taxpayer communications.

AI tools are now embedded within:

• Audit selection models for large partnerships and high‑income individuals

• Automated matching of third‑party information returns

• Drafting and analysis support for revenue agents during examinations

Importantly, the IRS has formalized this shift through a comprehensive AI governance framework, underscoring its intent to scale AI responsibly across compliance functions.

For institutions subject to extensive U.S. tax reporting, this means discrepancies are more likely to surface earlier and with less manual tolerance.

Brazil: AI to Accelerate Tax Rulings and Reduce Appeals Backlogs

Brazil provides a complementary perspective, applying AI not just to enforcement, but to tax dispute resolution itself. In April 2026, Brazil’s Administrative Council of Tax Appeals (Carf) announced the rollout of its internally developed AI system, Iara (Artificial Intelligence in Administrative Appeals), designed to reduce the average time required to adjudicate tax cases.

Historically, administrative tax appeals in Brazil could take nearly four years. The new system aims to help Carf meet legally mandated decision timelines by:

• Analyzing prior jurisprudence

• Supporting consistency in rulings

• Reducing procedural bottlenecks in high‑volume appeals

While initially positioned as a decision‑support tool rather than an automated adjudicator, Iara reflects a broader global objective: speeding up tax outcomes while maintaining enforcement credibility.

A Broader OECD Pattern: AI as the New Baseline

These developments are not isolated. According to the OECD, tax administrations are among the most mature government users of AI globally, applying it to:

• Risk scoring and audit prioritization

• Detection of fraud and evasion

• Automated case handling and grouping

• Pre‑filing and post‑filing data validation

In many jurisdictions, AI systems are now designed to flag issues before a return is finalized, raising the bar for data accuracy and internal controls at financial institutions.

Why Financial Institutions Are Turning to Third‑Party AI Tools

Against this backdrop, financial institutions face a critical decision: build AI compliance tooling in‑house, or adopt specialized third‑party solutions. For most organizations, building internally is neither practical nor scalable. Tax compliance AI requires:

• Continuous monitoring of regulatory changes across jurisdictions

• Trained models aligned to local documentation and validation rules

• Explainability, audit trails, and governance safeguards

• Ongoing retraining as tax authority behavior evolves

Third‑party compliance platforms increasingly fill this gap by embedding AI directly into operational workflows to handle document classification, data validation, change-in-circumstances tracking, and exception management, without requiring firms to design or govern models themselves.

Just as tax authorities are centralizing expertise and tooling, financial institutions are recognizing that leveraging specialized providers reduces operational risk, accelerates deployment, and aligns processes with how regulators now operate.

The Bottom Line

Japan, the United States, and Brazil each demonstrate a different application of AI in tax administration, but the direction of travel is the same. Tax authorities are moving faster, reviewing more data, and relying less on manual review.

For financial institutions, the takeaway is not simply that AI is “coming.” It is already embedded in enforcement, audits, and appeals.

Institutions that rely on manual tax documentation processes, or attempt to build bespoke AI solutions in isolation, risk falling out of sync with regulators’ expectations. Third‑party AI‑enabled compliance platforms offer a pragmatic path forward: bringing the benefits of AI to tax operations without the cost, complexity, and governance burden of building it alone.

TAINA can help.

If you’d like to see how TAINA can simplify and streamline your CARF and CRS compliance journey, we’d be delighted to request a demo.

To stay up to date with our latest insights on tax compliance, automation and regulatory change, sign up for our industry newsletter.