Search has gotten good enough that filenames feel optional. Then you go looking for the roof warranty and find Scan_20220914.pdf, document (3).pdf, and IMG_8842.pdf, and search can't help because none of them contain the word "roof."
That's the gap. Search works on what's in a file — and scanned documents, photos of paperwork, and many PDFs contain no searchable text at all. For those, the filename is the only handle you have.
Here's a naming convention that takes about five seconds per file and covers the cases that matter.
The format
YYYY-MM-DD-what-it-is-who-its-with.pdfReal examples:
2024-04-15-auto-insurance-policy-state-farm.pdf
2024-01-31-w2-2023-northern-medical.pdf
2023-09-08-roof-warranty-adirondack-roofing.pdf
2025-06-12-lease-agreement-maple-street.pdf
2024-11-03-lab-results-bloodwork-dr-patel.pdf
2022-03-01-car-title-honda-crv.pdfRead one of those and you know exactly what it is without opening it. That's the whole objective.
Rule 1: Date first, in YYYY-MM-DD
This is the rule that does the most work.
Why date first: it makes alphabetical sorting and chronological sorting the same thing. Sort any folder by name and you get a timeline, in any program, on any system, forever.
Why this specific format: it's the only date format that sorts correctly as text.
-
April-15-2024sorts next toApril-2-1998 -
04-15-2024sorts next to04-15-1998 -
15-04-2024means something different in half the world -
2024-04-15sorts exactly where it should, everywhere
It's also an international standard, so 2024-05-06 has one unambiguous meaning rather than two.
Which date to use: the date on the document, not the date you filed it. A 2023 tax form filed in April 2024 is 2023-something if it's the tax year, or the actual document date if that's what matters. Pick whichever you'd search by and stay consistent.
When you don't know: approximate. 2019-approx- is dramatically better than nothing.
Rule 2: Say what it is in plain words
The middle of the filename should describe the document as you'd describe it out loud.
auto-insurance-policy
w2
roof-warranty
lease-agreement
lab-results-bloodwork
car-titleNot codes. 2024-04-15-AIP-SF.pdf saves eighteen characters and costs you the ability to ever find it. You will not remember what AIP meant.
Modern systems allow long filenames — 255 characters. Use them. Being descriptive costs nothing.
Rule 3: End with who or what it's about
-state-farm
-northern-medical
-adirondack-roofing
-honda-crv
-maple-streetThis is what separates your three insurance policies from each other, and it's what you'll often search for. When the roof leaks, you might search "roofing" before you search "warranty."
Rule 4: Hyphens, lowercase, nothing exotic
Hyphens, not spaces. Spaces work fine on your desktop and break in a surprising number of other places — web links, command lines, some backup tools, some cloud services, some older systems. Hyphens work everywhere and read just as well.
Lowercase. Some systems treat Policy.pdf and policy.pdf as different files; others treat them as the same. That inconsistency causes real problems when moving between Mac, Windows, and cloud services.
Never use: / \ : * ? " < > | — all reserved or problematic somewhere.
Avoid underscores as separators if you can, though they're harmless. Hyphens are more readable at a glance because underscores can disappear under an underline in some contexts.
Rule 5: Never put status in a filename
lease-FINAL.pdf
lease-FINAL-v2.pdf
lease-FINAL-REAL-signed.pdf
lease-FINAL-USE-THIS-ONE.pdfEveryone recognizes this. Everyone still does it.
The problem: status changes, filenames persist. "Final" was true for about a day.
Status belongs in folders, not filenames:
04-PROJECTS/House Sale/
drafts/
signed/Or, when you genuinely need versions, use dates — which is what the convention already gives you. 2025-06-10-lease-draft.pdf and 2025-06-14-lease-signed.pdf are unambiguous and sort in order.
Rule 6: Don't rename everything you own
This is the most important practical rule, and the one that separates a convention you'll use from one you'll abandon on day three.
You do not need to rename 30,000 files. Nobody does that.
Apply the convention to:
- Documents you'll need to find deliberately — anything financial, legal, medical, or property-related
- Scans, which have no searchable text and no meaningful automatic name
- Anything you'd struggle to identify from its current name
- New files going forward
Skip:
- Photos from your camera (
IMG_20240518_142233.jpgalready contains a date, and photo apps handle these) - Files inside application folders
- Anything you'd only ever browse to rather than search for
- The mass of old files in your
99-TO-SORTfolder
The realistic target is a few hundred well-named documents out of tens of thousands of files. That's where all the value is.
Rule 7: Rename at the moment of filing
The right time to name a file is when you're saving or filing it — you already know what it is, and you're already making a decision about where it goes.
The wrong time is later, in a batch, when you have to open each file to remember.
This is why the "ask where to save each file" browser setting pairs so well with a naming convention: the save dialog is already open, the filename field is already there, and typing a real name costs three extra seconds.
Variations for specific types
Recurring annual documents — put the period, not the download date:
2024-taxes-federal-1040.pdf
2024-taxes-state-ny-it201.pdf
2023-taxes-federal-1040.pdfMonthly statements — year and month is enough:
2026-01-chase-checking-statement.pdf
2026-02-chase-checking-statement.pdfMulti-page scans of one thing — number them:
2019-04-passport-scan-01.pdf
2019-04-passport-scan-02.pdfThings with no meaningful date — lead with the category instead:
recipe-grandma-rose-tourtiere.pdf
manual-samsung-dishwasher-dw80r.pdfFor reference material you'll browse by topic rather than time, date-first is the wrong choice. Use it where chronology matters and skip it where it doesn't.
Renaming in bulk
When you do need to rename many files at once, don't do it by hand.
Mac: select multiple files in Finder, right-click, choose Rename. You get find-and-replace, add-text-before-or-after, and sequential numbering.
Windows: select files and press F2 for basic sequential renaming. Free tools handle more complex patterns.
Always preview before committing, and work on a copy the first few times. A bulk rename applied with the wrong pattern to two thousand files is a genuinely bad afternoon.
The test
A good filename passes this: someone else in your household could find the document you're describing, without asking you.
"It's the auto insurance policy" → they search insurance → they find 2024-04-15-auto-insurance-policy-state-farm.pdf → done.
That test is the whole point. Not neatness — findability, by someone who isn't you, at a moment when you're not available to explain.
Next in this series: How to Organize Important Documents, Birth Certificates to Tax Returns