Subject lines aren't always easy to write, but following the proven practices given below will help you avoid the common mistakes and sharpen your email subject lines.

Chisel your subject

Short and simple

Less is more when it comes to a subject line. A smart subject line has around four to six words at the maximum.

Spell check

This is easy to overlook, but even a typo will affect your open rates. Make sure to check for spelling and grammatical mistakes in the email subject and message.

Add pre-header

Inbox providers of your email recipients generally take the first few lines of your email message and set it as pre-header. It may include salutations or other lines you don't want to show up in the inbox view. You can set your customized pre-header when creating a campaign.

A/B testing

Test your emails for different subject lines using A/B testing. You can pick the line with better responses.

Relevant content

Your email subject and message should be relevant. If your email message is about a webinar, then the subject should also talk about the webinar. 

Mobile responsive

Most of your subscribers are likely to open emails in mobile devices. So, make sure your emails are mobile-friendly. While testing your emails, try opening emails from your mobile devices and check if the email looks fine.

Subject personalization

You can personalize your emails to make your subscribers feel more engaged with Zoho MarketingHub's merge tags. You can easily add the merge tags for subscribers' first and last name by clicking on the  Personalize option next to  Subject text box while creating a campaign. 

Emojis

Using emojis have varied results depending on the audience and how well you use them. For email clients which don't support emojis, the symbol ☐ is displayed. So, know how your subscribers will view your emails and then decide on including emojis. 

Things to avoid

All CAPS

Writing in all caps is an equivalent of yelling at your subscribers. All caps may stand out in the inbox, but it'll give a negative impression to your subscribers. Also, spam filters consider subject line with all-caps as suspicious.

Faking Re/Fwd tags

Including “re” or “fwd” in email subject might appear clever, but it misleads your subscribers and creates mistrust. Also, anti-spam services are smart and can easily identify fake RE: and FW: tags. To learn why you should avoid faking re/fwd tags and how anti-spam services detect it,  click here .

Excess punctuation

Too many punctuation marks in the subject line is considered suspicious by spam filters as phishing emails generally have excessive punctuation marks. 

False promises 

On opening emails with false offers in email subject, subscribers will either unsubscribe or mark them as spam. If you're giving an offer for a few products, state it clearly in the subject. 

Aggressive statements

Demanding your subscribers to open your emails will have a negative effect and lead to spam complaints. Subject lines seeking help, emergency, sensitive information, and other favors are considered suspicious by subscribers and spam filters. 

Words to avoid using in a subject line