Japan’s TDnet Expands XBRL Requirements from July 1, 2026

What’s Changing

Japan TDnet XBRL requirements are expanding from July 1, 2026, with updated specifications for disclosures submitted through the Timely Disclosure Network (TDnet).

At a glance, it may seem like just another regulatory update. But if your team is involved in financial reporting for Japan, this shift goes deeper.

It moves reporting from summary-level tagging toward more detailed, structured financial disclosures — extending XBRL to cover quarterly financial statements.

Historically, TDnet only required XBRL for the earnings summary (Kessan Tanshin) and forecast revisions. The rest of the financial report was often submitted as a PDF or HTML.

1. The Expansion: Effective July 1, 2026, the TSE will require full financial statements (Balance Sheets, Income Statements, etc.) to be submitted in Inline XBRL format for quarterly and annual earnings reports.
2. Effective Date: This applies to reports for fiscal periods beginning on or after April 1, 2026.
3. The Technology: JPX is moving to a new “TDnet Earnings Taxonomy” (the 2026-01-31 version) which aligns with the FSA’s EDINET taxonomy but adds specific disclosure requirements unique to the exchange.

These updates form part of the evolving Japan TDnet XBRL requirements, as outlined by JPX.

Does This Apply to You?

This update is relevant if you are:

1. A company listed on the Tokyo Stock Exchange (TSE)
2. A listed Real Estate Investment Trust (REIT)
3. Part of a finance, compliance, or reporting team supporting Japan disclosures
4. Managing reporting across multiple geographies or teams

If your organization is impacted by Japan TDnet XBRL requirements, this is something to start preparing for.

Stakeholders & Affected Companies

The primary stakeholders are JPX/TSE, the FSA, software vendors (who must update tagging tools), and institutional investors/analysts who consume this data.

How many companies are affected? As of April 2026, there are approximately 3,924 listed companies on the Tokyo Stock Exchange. The mandate generally covers all domestic companies listed on the three main segments:

1. Prime Market: ~1,571 companies (The global “blue chips”)
2. Standard Market: ~1,580 companies
3. Growth Market: ~598 companies

What Your Team May Need to Adjust

If your organization is working with Japan TDnet XBRL requirements, you’re likely already using TDnet for:

• Earnings reports and corrections
• Earnings and dividend forecast revisions
• Corporate governance disclosures

For earnings reports that include a quarterly accounting period beginning on or after April 1, 2024, HTML versions are also submitted alongside XBRL.

What changes from July 1, 2026 is the depth and scope of tagging.

With quarterly financial statements coming into scope, teams will need to:

1. Work more closely with taxonomy requirements
2. Ensure data consistency across reports
3. Manage more detailed tagging within existing timelines

Technical Resources: What JPX Has Published

JPX has made available two distinct sets of technical materials to support implementation.

The first covers existing TDnet reporting — earnings reports, corporate governance reports, and earnings summary preparation. This includes preparation guides for earnings summary reporting instances and company extension taxonomies, taxonomy rules and explanations, item lists, and sample instances for both earnings reports and corporate governance reports. These guides are primarily available in Japanese only.

The second is a dedicated package for the new quarterly financial statements scope, effective July 1, 2026. This includes its own management policy, preparation guides for report instances and submitter-specific taxonomies, a quarterly financial statements item list, taxonomies, and sample instances. These have been published as advance releases and their contents remain subject to change before the effective date.

For both packages, sample instances are published without guarantee of account validity or numerical consistency.

 What This Means in Practice

On paper, it’s an extension of what you’re already doing.

In practice, teams often run into:

1. Working with Japanese-language taxonomy documentation
2. The transition to Inline XBRL is significant
3. Coordinating between local and global reporting teams
4. Managing validation, review, and last-minute changes
5. Keeping tagging consistent across reporting periods

Implications for J-REITs

There is a very specific and heavy focus on J-REITs (Japanese Real Estate Investment Trusts) in the 2026 expansion. Because REITs operate differently than standard corporations—focusing on property portfolios rather than traditional product sales—the new mandate hits them with a unique set of technical requirements.

Here is the breakdown of the “special focus” for REITs:

From PDF to Structured Property Data

The biggest change for J-REITs is the “body” of the Kessan Tanshin (Earnings Summary).

1. The Status Quo: Currently, J-REITs provide a summary table in XBRL, but the most important data—the Property List (Portfolio), which includes occupancy rates, rental income per property, and appraisal values—is usually buried in a PDF or a flat HTML page.
2. The 2026 Mandate: These property-level details must now be tagged in Inline XBRL. For a REIT with 100+ properties, this means thousands of new data points (tags) that were previously invisible to automated analysis tools.

The “Distribution per Unit” (DPU) Nuance

Unlike regular companies that report “Dividends,” J-REITs report Distributions.

1. The new taxonomy (2026-01-31 version) includes specific elements for “Distributions in excess of earnings,” a common feature in J-REITs where they distribute cash from depreciation.
2. Accurately tagging these calculations is critical because global real estate analysts use these specific XBRL tags to feed their valuation models.

Alignment with ARES Standards

The Association for Real Estate Securitization (ARES) in Japan has its own voluntary disclosure standards. The TSE is working to ensure the new XBRL taxonomy aligns with these industry-specific “Global Best Practices.” This adds a layer of complexity: companies must ensure their XBRL tags match both the TSE/TDnet rules and the ARES guidelines.

Conclusion

The Japan TDnet XBRL requirements published by the Japan Exchange Group (JPX) include updated XBRL specifications for TDnet, covering taxonomy rules, item lists, and document file specifications, with application from July 1, 2026.

These Japan TDnet XBRL requirements include specifications related to quarterly financial statements and are accompanied by preparation guides, taxonomy materials, and sample instances.

Organizations submitting disclosures through TDnet will need to refer to these updated materials as part of their reporting process.

More info here