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The search requirement under Japan's Electronic Books Preservation Act — three fields, ranges, combinations, and how to meet it

The search requirement of Japan's Electronic Books Preservation Act means that stored electronic transaction data can be searched by three fields (transaction date, amount and counterparty), that dates and amounts can be searched by range, and that two or more fields can be combined (National Tax Agency Q&A, Q48).

Updated 2026-09-17. Based on the National Tax Agency's Electronic Books Preservation Act Q&A [Electronic transactions] (July 2026). "Q" numbers below refer to that Q&A. This page explains requirements of Japanese law.

Key points

The three parts of the search requirement

The National Tax Agency lists the following three search capabilities (Q48).

  1. Search by three fields. You can use the transaction date (or another date), the amount and the counterparty as search conditions. The date is normally the transaction date, but for a document that covers a month of transactions the issue date or receipt date is acceptable (Q55). The amount normally follows your bookkeeping method (tax-exclusive or tax-inclusive), but the amount printed on the document is also acceptable (Q57).
  2. Search dates and amounts by range. You can narrow down with an upper and lower bound, such as "1 January to 31 March 2024" or "100,000 to 500,000 yen".
  3. Combine two or more fields. You can narrow down with any two or more fields, such as "counterparty is (株)霞商店 and the transaction is in January 2024". Searching by one field and then narrowing that result by another field also meets the requirement (Q49).

When the search requirement is waived

Not every business has to meet all three parts. There are two levels.

If you can respond to a download request: ranges and combinations are waived

If, during a tax audit, you can respond to a tax official's request to download (show or submit) the electronic transaction data, range searches and combined searches are not required (Q48). Only "search by three fields" remains. The file-name method assumes this level (Q50).

If either of the following applies: all three are waived

Only the search requirement is waived. Keeping the data itself and taking measures against tampering are still required. Even when the search requirement does not apply, consistent file names save time when you look for a document yourself or hand files to your accountant.

Ways to meet it, compared

As methods that do not need dedicated software, the National Tax Agency describes two: using file names and keeping an index book (Q50). Accounting or document management software can also meet it.

Method What you do Suits you when Watch out for
File names Put the date, counterparty and amount in the file name in a consistent order (for example 20240131_(株)霞商店_110000.pdf). Find files with the operating system's search and sorting. Up to a few dozen files a month. You do not want another piece of software. Range and combined searches are replaced by responding to download requests (Q50). With YYYYMMDD dates, sorting by name sorts by date, which makes a period easy to pick out.
Index book Enter the date, amount and counterparty one row per file in a spreadsheet, and use serial numbers as file names. Filters give you range and combined searches. Many files. You often filter by amount or date. Your sales exceed 50 million yen and you do not want to rely on download requests. Data entry takes time. Dates and amounts entered as text cannot be searched by range. Keep rows and files from drifting apart.
Accounting or document management software Import the data and use the software's search for fields, ranges and combinations. You already keep your books in that software. Many files, several people handling them. It costs money. Data you forget to import does not meet the requirement. Check how to move the data before switching products.

You can also do both: file names for everyday searching, and an index book for range and combined searches. On the paid plan, Dencho Rename produces both at once.

Which one to pick

  1. If your sales in the base period are 50 million yen or less and you can respond to a download request, the search requirement does not apply. We still recommend putting the date, counterparty and amount in the file name so files are easy to find.
  2. If your sales exceed 50 million yen and you handle up to a few dozen files a month, file names are enough. Keep the data in one place so you can respond to a download request.
  3. If you have many files, or often filter by amount or date, keep an index book or use your accounting software's search.

Frequently asked questions

Is sorting files into folders enough?

One folder per counterparty with file names of "date_amount" is an example given by the National Tax Agency (Q50). Splitting into folders is fine as long as the folder name and file name together give all three fields. If the folder name and file name together do not tell you the date or amount, you cannot say the files are searchable by three fields.

Do I need special software to search?

No. With the three fields in the file name, the search and sorting in Windows Explorer or macOS Finder are enough. For an index book, the filters in Excel or Google Sheets are enough.

What does "transaction date or another date" mean?

The date of the transaction is the default. For a document that covers a month of transactions, the document's issue date or receipt date may be used instead. Whichever you use, keep it consistent within the tax period. If you use the issue or receipt date, make the amount searchable by the document total as well (Q55).

Is the amount tax-inclusive or tax-exclusive?

Following your bookkeeping method (tax-exclusive or tax-inclusive) is the default, but the amount printed on the document is also acceptable (Q57). Pick one and use it for every file.

What else is required besides search?

Measures against tampering (a timestamp, a system that keeps a history of corrections and deletions, or written office rules), the ability to display or print the data promptly, and, if you use software you developed yourself, a document describing that system (Q18). See "What is required for keeping electronic transaction data" on the file naming rules page.

Prepare for the search requirement with Dencho Rename

Drop invoice and receipt PDFs, or photo and scan images, into Dencho Rename and it reads the date, amount and counterparty from the text, renames every file in a consistent order, and returns them as a ZIP (PDFs with embedded text are free, up to 5 files at a time; reading photos and scans is a paid feature). On the paid plan it also produces an index book CSV with the same contents, so you are covered by both the file-name method and the index book method. Files are processed only inside your browser and never uploaded.

Use the tool (free) See pricing File naming rules How to make an index book

Sources