Email subject line codes

Subject lines. The menace of writing e-mail. How to actually write something meaningful in them before I actually know what I am gonna write about?

During recent years I started using little abbreviations in the beginning of the subject line in my e-mails to classify them at least into some categories that would allow already estimating what this is about.

When going through my Sent-folder it also allows me to quickly identify an email with attachments for example. Or e-mails where I asked for a question, but never got an answer to (based on what I remember).

Since I’ve been asked about a list of the common ones I use, I felt pressured to sit and write down this method I use.

I settled for English as language in those (though I mix it sometimes), because it reduces the list and variety of possibilities I have to choose from.

All is down to personal preference of course and under constant adjustment to the current needs.

So behold and gaze at my list:

Common ones


What I use it for


Informational e-mail. I do not expect a reaction from anyone to this, but you might want to read it.


A request. In this e-mail I want something from you. Something you have to do or that involves some work and uses your time.


Questions. Not requests. Something I think you could be able to answer or help me out with.


While the e-mail might be all over the place, there’s actually some attachment to it that you should pay attention to. Definitivly look at it.


I am lazy and sent you most likely only a link in this email to something else I’d like you to see.


A meeting request. Or some sort of. Well to meet is the topic of this one.

Rarely used ones


What I use it for


A test email. Can be ignored.


Announcing an error or a bug to someone who can do something about this.

The way I use it is quite simple actually. You might get an email with a subject line like this from me:

[INF] Change of name and address

This is an example from real-life. In the e-mail this line is from I inform about recent changes in address and naming to somebody else. If they do something with that information is up to them, so I would not use REQ for this, unless I depend on it.

Another example:

[REQ] Invoice 201817

Guess what? That email is about invoice 201817 and I need you to act on something related to it. You might want to put aside some time for this and not just fly over it and delete it.

A last one:

[FIL] Measurement for Wardrobe

As the subject states a file is attached with (probably) contains the measurements for wardrobe. With a different code (like [QUE] for instance) you would realize that that would be some questions, but not the measurements that you need to look at. Unless you are looking for the email with the questions.

This technique serve me well so far and I rarely get any questions about it. Most people probably tend to ignore it anyway. That’s fine with me. But it helps me to sort through my emails faster. And if this is useful, somebody might actually adopt it or find an even better approach.