Get more leads with cold emails

Automate & personalize your outreach to scale and convert more.

Try For Free
No credit card required*

16 Tips to Write Killer Email Subject Line

7 min read
7504 reads

The subject line of an email is the first thing to gain the attention of the recipients. It often becomes the deciding factor for an opening of the emails. An email should always have a good and convincing subject line. Emails lacking subject line is either ignored or delete.

A catchy subject line leaves an appealing impression on the recipients. It helps in gaining recipient’s attention and persuading him to open the mail sent. Enlisted below are few tips for drafting killer subject line.

1. It should be the first thing to be decided

Many times subject lines are not given much importance. It is drafted after the body of the email is ready to be sent. This is one of the biggest mistakes that one can do. We all know that the first impression is the last impression. And the first and foremost thing that your recipients get to read in your mail is its subject line. It has to be given importance and should be the first line to be drafted.

2. Personalize the subject line

A personalized subject line is always more catchy. It gives a feeling of personal attention to the recipients. When sending emails from a company, one has to send the same emails to multiple recipients. A personalized subject line for each recipient should be drafted, giving an impression that the mail is drafted for each recipient individually.

It is advised to use the name of the recipient, either first or last name, in the subject line. Adding the city name of the recipient is also a good practice.


“Happy Birthday Lindsay – Surprise Inside!”

3. The shorter the better

Short subject lines can be read by the subscribers at a glance. Moreover, mobile phone have become the primary email reading device. Short subject lines are easier to be read on the mobile.


Draft a subject line of maximum 50 characters. Let it be short.

4. Make it informative

The subject line should be able to give some idea to the recipients about the content of the email. This will help the subscribers choose wisely, and decide if the mail is catering to their requirements. Guesswork done by recipients causes irritation to them and they tend to ignore your emails over time.


“11 Mind-Blowing Copywriting Hacks To Improve Your Website”

5. Fresh subject lines can make a difference

People get bored seeing the same subject line each time. So, make it a practice to use the new subject line each time a new mail is sent.

Newsletters are the best example to explain this. Its opening rate is high when the first few emails are sent but tends to decrease with the passage of time. The reason most is that the same subject line is used perpetually. Make the fresh subject line every time, and include some pointers to what the newsletter contains.

Example: Avoid the following

“This week newsletter from SoftwareSuggest”

Check some of the best email subject lines for sales templates.

6. Induce curiosity

The subject line should be capable enough to induce curiosity in the recipients. It should be interesting to trigger them to know more about the mail.

Though it should give some idea of the mail content, the whole content of the mail should not be disclosed. It should make the receipts curious to check out the whole content of the email.


“Reason for 10% increase in inflation”

7. Preference should be given to important words in the subject

Every one of us has to go through lots of emails everyday. We hardly give a second or two to decide if the mail is worth opening. Let important words stating the matter of email be included in the subject line.

“Almost 55% of editors in our guest post pitch survey have said, when it comes to emails about guest posting, they prefer straight forward subject lines like “Guest post pitch” or similar. They know straight away what the email is about and will open it.” Anita, Point Visible

8. Filler words to be eliminated

Avoid using words like um, uh, er, ah, like, okay, right in the subject line. These can be included in the emails. As the subject lines have to be short, each and every word is precious. Also, filter word can make your email end up in the spam box.


“Uh-oh, your prescription is expiring”

9. Make it simple

Simple subject lines are always admired. It is easy for the recipients to understand and read. Making it in poetic will not be to your advantage.

Example: Avoid the following

“How many boards, could the Mongols hoard if the Mongol hordes got bored?”

10. Logical keywords to be embedded

Many times the recipients do not check the mails the moment they receive it. They have a practice of putting the mails to folders and they go through it later. Logical keywords related to the topic of the emails help to make the searching process of the emails easier, when it is required.

11. State your references

Stating the name of the person or company who has referred you in the subject line is always a good practice. It helps in grabbing recipient’s attention. Many times it is reserved for the content of the email. However, one should also include it in the subject line.


“I found you through [referral name]”

12. Advantages to the recipients can be stated

Advantages to the recipients stated in the subject line act as a trigger to induce them to go through your mail. If some discount or opportunity has been provided in the mail, it is always advised to mention it in the subject line. For any offer or discount, the percentage of discount can be mentioned on the subject.


“50% off if you join now!”

13. Specify if any response is awaited

It is always better to specify in the subject line if any response is awaited. Phrases and words like “please reply”, “your suggestions are most valued on [this topic]”, etc. can be added to subject line.

14. A deadline can be stated

The deadline can be stated saying, “Please reply by [day/date]”. This will convey the urgency of reply needed from the recipient’s side. For long emails this works well, a recipient will have to go through the email before the set deadline.This practice is followed by the government agencies.


“Please submit your tax details before 1st June to avoid penalties”.

15. Don’t ask questions in the subject, having its answers in the mail

Asking question in the subject line with answers appearing somewhere in the mail is not appreciated. This is forcing your recipients to open your mail and obviously, your mails should be not aimed to do this. Rather going through your mails should be a wanted experience by your recipients.

16. Subject lines should not be in all capitals

Though capital letters grab attention easily and rapidly, but it is advised not to use all capitals. In written communication, it is considered to be yelling at your recipients and obviously, that is not your motto.


Example: Avoid


Tip – It is advised to read the subject line before you send your email. Remember!! It is the first thing the recipient reads and thus should be impressive and informative.

This article will help you draft the perfect subject line, however, the first step of the prospecting is to find the prospects email address.

Skyrocket your conversion rates with cold emailing

Email address is not valid

Recent Articles