How to make an index book — meeting the search requirement with a spreadsheet

Updated 2026-09-14. 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

An index book is a list with one row for each invoice, receipt or other document you keep as data.
The National Tax Agency explains that entering the transaction date (or another date), the amount and the counterparty in a spreadsheet such as Excel meets the search requirement, if the spreadsheet can search by range and by a combination of two or more items (Q50).
Each row must be linked to its data file. In the National Tax Agency example, files are named with serial numbers 1, 2, and so on (Q50).
Unlike putting the date, amount and counterparty in the file name (file naming rules), serial numbers are enough for file names, so there is no naming to think about. In exchange, you need to fill in the list.

CSV template (no sign-up)

A template with the same columns as the index CSV made by Dencho Rename, with column headings and one example row. It is UTF-8 with a BOM, so Excel opens it as is.

Download the CSV template

The National Tax Agency also publishes a sample index book in Excel format with five columns: serial number, date, amount, counterparty and note (reference materials, in Japanese).

Columns

Column	What to enter	Example
No.	A serial number starting from 1. If files are named by serial number, use the same number	1
Transaction date	The transaction date or another date. Entered as `2024-01-31`, Excel treats it as a date and can filter by range	2024-01-31
Counterparty	The counterparty name, spelled consistently	株式会社サンプル
Amount (tax incl.)	Digits only. No 円 or other characters	110000
Document type	Invoice, receipt, purchase order, etc.	請求書
Document number	An invoice number or similar. Leave blank if none	INV-0012
Saved file name	The file name of the saved data. This column links the row to the file	20240131_株式会社サンプル_110000.pdf
Original file name	The file name as received. Useful when searching by an email attachment name	invoice_final_v2.pdf
Note	Free text

Only the transaction date, amount and counterparty columns relate to the search requirement. The other columns make documents easier to find later.

Amounts should normally match your bookkeeping method (tax-excluded or tax-included accounting), but the amount written on the document is also acceptable (Q57). If you enter tax-excluded amounts, rename the heading to "Amount (tax excl.)" to avoid confusion.

Steps

Decide on a folder for electronic transaction data.
Put the data you receive in that folder and name each file with a serial number (1.pdf, 2.pdf, …) or with the date, counterparty and amount.
Open the template and enter one row per file with the date, counterparty, amount and so on.
Save it in Excel format (.xlsx). If you keep it as CSV, choose "CSV UTF-8" (other CSV formats may show garbled characters when opened on another computer).
Take a measure against tampering. An index book is for searching and is not enough on its own. One option is to set internal rules and follow them (Q19, Q30).

Searching in Excel

Select the heading row and turn on Filter on the Data tab. A ▼ appears on each heading; use it to filter.

Date range: ▼ on Transaction date → Date Filters → Between, then enter the start and end dates.
Amount range: ▼ on Amount → Number Filters → Between, then enter the lower and upper limits.
Combining two items: filter by Counterparty, then filter further by Transaction date or Amount. Searching by one item and then narrowing the results by another also meets the requirement (Q49).

In Google Sheets, Data → Create a filter works the same way.

Common mistakes

Dates are entered as text. Entries such as 2024.1.31 or "Jan 31 invoice" are not treated as dates, so you cannot filter by range. Enter 2024-01-31 or 2024/1/31.
Amounts contain text. Entries such as 110,000円 or 11万円 are not treated as numbers, so you cannot filter by range. Enter digits only.
Rows and files get out of sync. Renumbering after sorting, or renaming only the files, makes it impossible to tell which row belongs to which file. Once assigned, do not change serial numbers.
Date and amount do not match for monthly documents. Either enter each transaction's date and amount, or the issue (or receipt) date and the total amount, and stick to one way (Q55).
Only the index book is made, with no measure against tampering. That measure is required separately from the search requirement (Q18).

Make the index book with Dencho Rename

On the paid plan, Dencho Rename creates an index CSV with the same columns as this template while it renames your PDFs. The Saved file name column holds each new name, so you do not have to link rows to files by hand. Files are processed only inside your browser and never uploaded.

Use the tool See pricing File naming rules