People get a lot of emails. Writing an effective subject line helps employees manage their time and stay focused on the right things.
Organizational emails from any business function (CEO, Communications, HR, Operations, Security, Maintenance, IT, etc.) must quickly help employees know:
- When to open it
- The topic (Yes, there should only be one topic per email – even when bundling.)
Basic anatomy of a subject line
- Prefix – signals the urgency and importance of the message
- Topic – gives a solid clue as to what the message is about (even if you’re taking a teasing approach)
How you use and balance these two parts will shape the effectiveness of your subject line.
Tip The most effective subject lines have 3-5 words (excluding dates). Except in rare cases, don’t exceed 7 words.
Step 1 – Categorize
Not all emails have equal value. Before you write the subject line (or even the email for that matter) you should know where the message sits in the grand scheme. Ask yourself: “Considering the big picture, how important is it that I catch an employee’s attention?”
There are four categories:
| Type | Definition | Examples |
|---|---|---|
| Critical | Time-sensitivity is in near future | Network being shut down for emergency repair Office closing due to severe weather |
| Important | Time-sensitivity that is not immediate | • Performance reviews are due • New product launching |
| Good to Know | Deepens employees’ understanding or engagement but isn't required for them to be able to do their work. | • CEO will be interviewed for article in local paper • Sales up/down in past quarter |
| Not so important* | Content makes no difference to employees' engagement or ability to do their work | • The form for requesting a desk move has been improved • There’s a new flavour of coffee in the cafeteria |
Step 2 – Build the subject line part by part
Critical content
1. Use a prefix* such as:
TIME-SENSITIVE:
IMPORTANT:
PLEASE READ NOW:
URGENT:
*Using all caps for the prefix only will make this stand out even more – provided it’s used sparingly and only when there truly is some urgency to the message.
2. Use two or three words to tell the reader about the topic. Examples:
Office closing
Security alert
Network shutdown
Performance reviews due
3. Add the time context either with an exact time and date or a relative time or date. Examples:
Today at 1pm
Early
December 31
Tomorrow from 3pm to 6 pm
That’s it! You’re ready to write your message!
Important content
1. Consider using a prefix such as:
Advisory:
Action Required:
Heads Up:
Notice:
Wanted:
You need to know:
Needed:
Deadline ahead:
2. Use one or two words to tell the reader about the topic. Examples:
Security reminders
New brand campaign
System maintenance
Performance reviews
That’s it! You’re ready to write your message!
Good to know content
This category is perfect for bundling messages. It helps control the number of emails sent, makes good use of employees’ time and can be a great way to reinforce big picture messages.
The following steps apply whether or not you decide to bundle.
1. This is the category where you can have a bit more fun with prefix. Examples:
Check it out!
Did you know?
Good to know…
Guess what?
If you’re interested…
2. Use 4-6 words to tell the reader about the topic. Examples:
(bundled) Summer charity events and dollars raised
(standalone) $5000 raised for XYZ Charity
(bundled) Service ‘n’ Stuff employees recognized by various professional associations
(standalone) Service ‘n’ Stuff project management office receives industry award
That’s it! You’re ready to write your message!
Not so important content
Stop. Don’t send an email!
As mentioned in Step 1, it’s more effective to share “not so important information” by:
- Posting it on the Intranet for people to access if and when they need it
- Asking managers to share it at a team meeting
- Bundling it with similar information in another email
Closing thoughts
Once you look at subject lines in their parts of prefix and topic, writing effective ones becomes easier and takes very little time. No matter what, always be sure to reflect the tone of the message to help set expectations (e.g. don’t use the prefix “Heads Up” if the message is about a restructure). Plus, if a date is warranted (see Step 2, Critical), include the day of the week to help eliminate any confusion. It’s worth the extra characters. (e.g. “Thursday, January 15” instead of “January 15”)
