Guide
File naming conventions for due diligence: a simple system that survives a long deal
Published October 21, 2026
Key points
- Start every file name with its index number, so the order in the room matches the order in the index.
- Use ISO dates (YYYY-MM-DD), so files sort by date automatically.
- Put the counterparty and document type next, in plain words a reviewer would search for.
- Mark versions and status at the end (v2, signed, draft), and never use "final".
- Agree the convention before the first upload; renaming hundreds of files later breaks Q&A references.
A due diligence file naming convention is a fixed pattern for naming every document that goes into a data room. It sounds trivial. In practice it decides whether a buyer’s lawyer can find the 2023 supply agreement in ten seconds or ten minutes, and whether “see document 4.2.7” in a Q&A answer still points to the right file a month later.
Most data rooms number documents automatically based on where they sit in the folder tree. A good file name adds what the number cannot: what the document is, who it is with, when it is dated and which version it is.
The pattern
One file name, five parts
- 01 Index number 4.2.7, matching the folder position in the room.
- 02 Date 2023-03-14, ISO format so it sorts correctly.
- 03 Counterparty Acme-Logistics, the other party or subject.
- 04 Document type Supply-Agreement, in plain words.
- 05 Version or status signed, v2, redacted, draft.
Example: 4.2.7_2023-03-14_Acme-Logistics_Supply-Agreement_signed.pdf
| Part | Example | Why it helps |
|---|---|---|
| Index number | 4.2.7 | Keeps order stable and matches the index export |
| Date | 2023-03-14 | Sorts by date and shows the document’s age at a glance |
| Counterparty or subject | Acme-Logistics | Makes the file findable by the name reviewers remember |
| Document type | Supply-Agreement | Search terms buyers actually type |
| Version or status | signed | Removes doubt about which copy is the operative one |
Rules that keep it clean
- Use the document’s own date, not the upload date. A lease signed in 2019 should say 2019.
- Use hyphens inside parts and underscores between parts. Avoid spaces and special characters such as
/ \ : * ? " < > |, which break on some systems. - Keep it short enough to read. Around 60 to 80 characters is plenty.
- Spell out abbreviations once in the index. “MSA” is clear to a lawyer, not always to an accountant.
- Never use “final”, “final2” or “FINAL-really”. Use version numbers and a status word.
Most rooms on our list renumber documents automatically when you move them. If yours does, you can leave the index number out of the file name itself and rely on the room’s numbering, as long as everyone cites documents by that number. 11 of the 11 providers list bulk upload that keeps folder structure intact, which makes the first load much faster.
Examples by folder
| Folder | Good file name | Weak file name |
|---|---|---|
| Corporate | 1.1.2_2018-06-01_Articles-of-Incorporation.pdf | articles.pdf |
| Financial | 2.3.1_2025-12-31_Audited-Financial-Statements.pdf | FS final v3 (2).pdf |
| Contracts | 4.2.7_2023-03-14_Acme-Logistics_Supply-Agreement_signed.pdf | Acme contract.pdf |
| Employment | 6.1.4_2024-01-15_Employment-Agreement_CFO_redacted.pdf | Jane Smith contract.pdf |
| IP | 7.2.1_2022-09-30_Patent-US-11234567.pdf | patent.pdf |
| Litigation | 8.1.3_2025-05-20_Smith-v-Company_Statement-of-Claim.pdf | lawsuit.pdf |
The employment example avoids putting a person’s name in the file name. Names in file names leak into notifications, activity logs and exports, which matters for privacy.
What a good name tells a reviewer before opening the file
Versions and redactions
Data rooms with version control let you replace a file while keeping its history. Use that, rather than uploading “v2” next to “v1”. Where the room does not keep versions, put the version at the end of the name and move superseded copies to an archive folder so reviewers do not rely on the wrong one.
Redacted documents should say so in the name. If both a redacted and an unredacted copy exist (for a clean team, for example), the status word makes it obvious which is which.
Setting it up
Introduce a file naming convention before the first upload
- Agree the patternWrite the five-part pattern on one page and share it with everyone who will upload.
- Build the index firstCreate the folder structure and numbering before naming files.
- Rename locallyRename files on your computer before upload; most rooms keep the name you upload.
- Bulk upload by folderUpload whole folders once they are named, so the structure stays intact.
- Spot-checkSort each folder by name and date in the room and fix outliers.
- Keep it goingName late additions the same way and add them to the right folder, not the root.
Quick checks before you invite anyone
- Every file starts with an index number or sits in a numbered folder.
- Dates are the document's own date, in YYYY-MM-DD format.
- No file is named "final" or "copy of".
- No personal names appear in file names where avoidable.
- Redacted copies are labelled as redacted.
- Superseded versions are archived or handled by version control.
Naming is part of setup; the set-up guide covers the rest, and the 11 providers we review differ in how they handle numbering, versions and bulk upload.
Frequently asked questions
Should file names include the index number?
It helps, especially if documents are downloaded or exported. If the data room numbers documents automatically and everyone cites that number, you can leave it out of the file name itself.
What date format should I use?
YYYY-MM-DD. It sorts correctly in every system and avoids confusion between day-month and month-day formats.
Is it OK to use spaces in file names?
Most rooms handle spaces, but hyphens and underscores are safer when files are downloaded, exported or moved between systems.
How do I name multiple versions?
Use version control in the room if it has it. Otherwise add v1, v2 and a status word, and archive superseded copies.
Should employee names appear in file names?
Avoid it where possible. Use a role or ID; names in file names show up in notifications and logs.