Bates numbering, explained: formats, conventions and a clean workflow

Bates numbering — named for the late-1800s Bates Automatic Numbering Machine, a hand stamper with rotating wheels — is the legal world’s page-identification system: a unique, sequential label on every page of a document production, so that “the email at SMITH-000412” means exactly one page to everyone in a case, forever.

If you’ve been asked to “Bates-stamp” documents for the first time, the good news is that the mechanics are trivial. The conventions are where new stampers go wrong, and the conventions are what this guide is really about.

Anatomy of a Bates number

A modern Bates number has two parts:

• Prefix — a short identifier, usually uppercase, tying the page to a producing party or matter: SMITH-, PLTF_, ACME-PRD-. In multi-party litigation the prefix is what tells productions apart, which is why protocols insist each party use a distinct one.
• Padded number — a sequential counter with leading zeros: 000001, 000412, 007293.

Together: SMITH-000412. The stamp goes in the same position on every page — bottom-right is the widespread default — in a size that’s legible but doesn’t collide with content.

The conventions that matter (and why)

Compiled from current e-discovery practice guides, July 2026:

Zero-padding is not decoration. ABC-000010 sorts after ABC-000009 in every file manager, review platform and spreadsheet. ABC-10 sorts before ABC-9 in most of them, because text sorting goes character by character. Since Bates numbers end up as filenames, load-file fields and citation strings, unpadded numbers cause real chaos in real cases.

Six digits minimum; eight for large matters. Six digits allows 999,999 pages under one prefix — enough for most cases, cheap insurance for all of them. Large litigation productions use eight. Running out of digits mid-production and switching format is precisely the kind of inconsistency protocols exist to prevent.

Numbering continues across productions. If your first production ends at ABC-001500, the second one starts at ABC-001501 — not back at 1. A Bates number identifies a page for the life of the case; restarting would make two different pages answer to the same name. Keep a simple production log: date, range produced, next available number.

The ESI protocol wins. Many cases negotiate an ESI (electronically stored information) protocol that specifies Bates format explicitly — prefix per party, digit count, placement, even font. If your case has one, it overrides every default in this guide and every default in any tool, including ours.

A clean stamping workflow

1. Stamp copies, never originals. Bates stamps are permanent page content by design. Keep a pristine set; produce from stamped duplicates.
2. Fix the documents first. Rotation, page order, flattening of filled forms — all of it happens before stamping, because edits after stamping risk orphaning or duplicating numbers.
3. Set prefix, digits, and start number from your production log.
4. Stamp, then record the ending number in the log before anything else happens.
5. Verify a sample: first page, last page, and a rotated landscape page if the set has one — the stamp should sit in the same visual corner, right side up, on all of them. (Rotated pages are where cheap stamping tools fail; the stamp ends up sideways or off-page.)

Common mistakes, from the review side

These are the errors that surface later, during review or at depositions:

• Restarting numbering per document or per production — creates duplicate identifiers; see above.
• Prefix drift — SMITH-, Smith- and SMITH_ in one production are three prefixes to a computer. Pick one string; reuse it exactly.
• Stamping over content. A Bates number that covers a date on an invoice creates an argument nobody needs. Use a margin placement that clears the page’s content; spot-check crowded pages and edge-to-edge scans.
• Stamping the privileged set. Documents withheld for privilege are logged, not produced — stamping them into the production sequence causes gaps or, worse, accidental production. Number what you produce.

Does the tool matter?

Less than the discipline does. Any tool that produces a permanent, consistently placed, zero-padded stamp — desktop software, review platforms, or a browser-based stamper — produces an equivalent artifact: a standard PDF with the numbers drawn into each page’s content.

What browser-based stamping changes is custody: the documents are stamped in your browser’s memory and never travel to a third-party server — no upload queue, no retention policy, no processing agreement to evaluate. For discovery material, that’s not a small point. The trade-off is scale: a browser comfortably stamps documents of hundreds of pages, but bulk productions of thousands of files belong in dedicated review platforms, which also generate the load files and logs that go with them.

Beyond litigation

Bates numbering long ago escaped the courtroom. Medical-records departments stamp chart productions; accountants stamp audit workpapers; real-estate closings stamp document sets. The convention travels because the problem travels: any time two people need to refer to one page among thousands with zero ambiguity, a prefix and a padded counter is still the simplest technology that works.