Our Research team analyzes the emails sent from users through MailChimp to find what practices result in the best open rates. The best email subject lines are usually short, descriptive, and provide the recipient with a reason to open your email. Keep your particular audience in mind and thoroughly test keywords and phrases to maximize subscriber engagement.
In this article, you’ll find tips to help you write subject lines, and learn about tools you can use to make your subject lines more engaging.
Tips for Subject Lines
- Include Localization
Personalize a message with a recipient's first or last name to improve open rates. MailChimp research suggests including a city name is even better.
- Use Different Subject Lines
Newsletters tend to start with high open rates, but these decrease over time. Keep your content fresh, and don’t repeat the same subject line for each campaign. If subscribers can’t tell something about your content from the subject line, they probably won’t open your campaign.
- Keep Subject Lines Short
Most people quickly scan subject lines to decide if they’ll open or ignore the email, so don’t expect subscribers to dig through your subject line to figure out if they’re interested. Keep your subject line to 50 characters or fewer.
- Use Promotional Emails Effectively
There are a few ways to increase subscriber engagement with promotional emails. Promote contests and giveaways in your campaigns to reconnect with inactive subscribers. Send subscribers a poll or survey to find out what type of content they’re interested in. Offer a free gift or service as an incentive to complete the poll or survey.
Customize Subject Lines
Our emoji picker and merge tags allow you to create a subject line that is fun and personalized.
To add emojis to your subject line, follow these steps.
- Navigate to the Setup step of the Campaign Builder.
- In the
Email subject field, click the Smile icon and choose the emojis you want to include.
Not all inboxes render emojis in the same way. Test your campaign or use the Inbox Preview to view your campaign in several inboxes before you send.
Use merge tags to personalize the subject line with content that is unique to your subscribers. For example, if you have a field in your list for the city where your subscribers live, use the city merge tag in the subject line and we’ll replace it with each subscriber’s city when the campaign is sent.
We don’t, however, support the use of conditional merge tags in subject lines. It’s always a good idea to test your merge tags before you send your campaign.
Test Subject Lines
MailChimp offers tools to help you write and test effective subject lines. Our Subject Line Researcher uses our extensive collection of subject line data to help you write a subject line, and A/B Testing Campaigns test the performance of up to three different subject lines.
Subject Line Researcher
Our free Subject Line Researcher tool tests different keywords to help you write an effective subject line. To use this tool in the Campaign Builder, follow the steps below.
To use the Subject Line Researcher, follow these steps.
- Navigate to the Setup step of the Campaign Builder.
- Click the
How do I write a good subject line? link under the
Email subject field.
- In the pop-up modal, click
Subject line researcher.
- Type several phrases into the
Subject line terms field and click
Search to populate results. For best results, enter one term or phrase per line and limit phrases to three words and keep the search broad.
MailChimp compares those terms to all subject lines ever used in our system, and displays a 5-star rating system for how the subject lines containing those terms performed.
Create an A/B Testing Campaign
Unlike the Subject Line Research tool, which tests your subject line against all subscribers on MailChimp lists, A/B Testing Campaigns test your actual subscribers to see what they like best.
A/B Testing Campaigns create up to three versions of your campaign to test how a small difference impacts campaign performance. Send two or three versions of your campaign with different subject lines to randomly selected parts of your list, and we’ll automatically send the campaign with the best open rate to the remainder of your list.
Other Factors that Affect Open Rates
It’s not just your subject line that affects your open rates. The sender and nature of your content can also impact your results. Here are some things to consider when you create your campaign.
- Maintain Your Subscribers' Interest
The success of your campaign depends on how well you maintain the interest of your subscribers over time. Create content, including subject lines, that engages your subscribers and meets their expectations.
- Consider the From Name
The from name can be as important as the subject line, because subscribers won’t open emails from people they don’t recognize. Use the from name to say who you are as the sender, and keep it consistent over time.
- Use Groups and Segments for Your List
Target subscribers with groups and segments so they get information that’s relevant to them. If your subscriber data indicates that someone is interested in vegetarian recipes, they probably won’t open an email with a subject line about the 10 best meat recipes. If subscribers provide information to help target your messages, use it.