Keep electronic files organized by using ISO 8601 date standards

A number of years ago I had a client who named his electronic files and folders using this format:

Name of file or folder 2007-07-31

I quickly realized that this made the files or folders much easier to organize. When used consistently, all the files or folders will be named and therefore organized by date. This is very handy when doing bookkeeping and accounting work, as it makes a given file very easy to locate. It also makes it easy to see if a particular file is missing. For example, I might request all of the checking account statements for a given year from a client. If I receive them all except one, using the above format makes it easy to recognize that a file is missing. Using a non-standard, ad hoc, make-it-up-as-we-go format, makes it take longer to locate particular files because they won’t be sequential. It also makes it harder to see if sequential or chronological files are missing from the sequence.

iso logoOnce I understood how much more efficient this method is, I began to use it right away. It wasn’t until just a couple months ago that friend explained where the standard came from. I thought my former client was a smart guy who made it up on his own! But it turns out that this is an accepted standard from the ISO, which stands for International Organization for Standardization. The standard comes from ISO 8601 Data elements and interchange formats – Information interchange – Representation of dates and times. 

The idea is to always use the year first, then the month, then the date. The year is always represented as four digits. The month and date are always represented as two digits. So January 1, 2020 would be represented like this:


Keeping two digits for the month and date is important, because using a single digit there won’t keep the files sequenced in a chronological way.

Most people who use the ISO 8601 format seem to include the dashes in between the fields. I actually prefer to omit the dashes, as they are unnecessary keystrokes. So for my own files and folders, I represent dates like this:


It it a little awkward to read at first, but doesn’t take long to become fluent in it. Either method is considered acceptable under the standard. If only the year and month are needed, this is an acceptable way to show them:


This would always mean January 2020, under this standard.

I do recommend for anybody working with PDFs or other electronic copies of bank statements, credit card statements, loan statements, etc., to use the ISO 8601 standard when naming their electronic files. For example, checking account statements from Citibank can be named like this:

  • Citi checking 2020-01-31
  • Citi checking 2020-02-28
  • Citi checking 2020-03-31
  • and so on.

The date should be the ending date on the statement. See how easy it will be to verify that all of the files are there, and to determine if any are missing?

You can read more about the ISO 8601 standard here.

Image credit: ISO Logo

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