Holiday Subject Line Insights to Boost Your Results
During the holiday season, even the most loyal customers may only give your messages a quick glance. So, it’s essential for email subject lines to communicate value and capture attention efficiently.
To identify compelling subject line tactics, we examined the subject lines of approximately 22,000 campaigns sent by retailers during the 2025 holiday season.
We organized the most commonly used words into six major themes and then correlated those word groups with open and click metrics.
Let’s look at each theme and its effectiveness.
Discount-Related Terms
The most prevalent category—discount-related terms—contains words like “off,” “sale,” and “deals.” Promotional language performed well, especially when it came to driving click-through rates.
Recommendation: Keep discount phrasing in your holiday subject lines, and make the value of each offer easy for subscribers to understand. Many consumers sign up specifically to receive discounts, including shoppers who subscribe only for the holiday season and then opt out afterwards.
Our data indicates that retailers are fulfilling subscriber expectations when it comes to delivering sales information, discount codes, and coupons.
Seasonal Phrases
Holiday phrases, such as “Black Friday” and “Cyber Monday,” were common. However, subject lines featuring these terms underperformed, especially on clicks.
In general, awareness of specific shopping occasions is high, even when brands begin promoting “Black Friday” deals in early November. These words reiterate what subscribers already know, potentially contributing to weak results.
Recommendation: Instead of using seasonal language in your subject lines, consider placing it after your brand in the sender field. For instance, you could try “YourBrand Black Friday,” “YourBrand Cyber Week,” or “YourBrand Holiday.” This tactic has become increasingly popular, not only during the holiday season but during other selling seasons too.
Adding holidays to sender names works especially well for brands with names of seven characters or fewer. Still, it can be effective for those with slightly longer brand names. If you’ve never used this approach before, test it this holiday season.
Urgency-Related Terms
This category, involving words like “ends,” “hurry,” and “final,” was the third most common after discount-related and seasonal terms. Surprisingly, urgent subject lines delivered only moderate results.
Urgency may be a victim of its own success. Because it is a powerful psychological motivator, marketers may overuse urgency, as evidenced by the rapid rise of “sale extended” messages.
Customers now largely expect sales to be extended, while simultaneously resenting “sale-ending” messaging that turns out to be false. In fact, deceptive urgency practices have been challenged in class-action lawsuits against retailers.
Recommendation: Use urgency more sparingly, and ensure that your sales tactics build customer trust and avoid legal risk. While brand-wide sales are easy for subscribers to understand and act on, explore other promotional strategies that have some nuance, such as:
- Channel-exclusive sales, such as sale prices that are only available in your app or a discount that is limited to SMS subscribers
- Discounts on future purchases or free e-gift cards for customers who spend $X
- Gifts of free points to loyalty program members
- 12 Days of Christmas campaigns, where a different product category or selection of products is on sale each day
Channel-Related Terms
Terms such as “online,” “site,” and “stores” appeared relatively infrequently but generated some of the highest click-through rates.
In recent years, brands have been promoting discounts that are only available in a particular channel, whether through SMS or email, in an app, or in stores. Exclusive discounts differentiate promotional channels and encourage opt-ins across platforms, a behavior that builds customer loyalty.
Recommendation: Use channel-exclusive offers to move excess inventory and encourage customers to shop across multiple touchpoints. Also consider a sender name extension, as recommended in the Seasonal section. For example, you could extend your sender name to “YourBrand App Only” or “YourBrand Stores.”
Personalization
Some campaigns mentioned “Firstname” or other phrases tailored to subscribers. Among the least used tactics, personalization correlated with strong opens and clicks.
The results are surprising: subject-line personalization once signaled that the email itself would contain relevant, individualized content, but years of superficial personalization weakened that expectation. The metrics indicate that attitudes are changing and meaningful personalization can still capture attention.
Recommendation: Test personalization frequently by adding subscribers’ names, product names, loyalty point balances, or other relevant details into your subject lines. However, subject-line personalization should always align with the email content. Otherwise, it may create false expectations and disappoint subscribers.
Loyalty Terms
Phrases related to loyalty programs, including “member” and “rewards,” were among the least common subject line themes. Loyalty was also the lowest-performing theme analyzed. Consumers value rewards programs, but these words generated weak member engagement.
Recommendation: Loyalty terms are another opportunity to move relevant language into your sender name (e.g., “YourBrand Rewards,” “YourBrand LoyaltyProgramName”), and then focus your subject line copy on discounts, channel-specific offers, urgency, and personalization.
Next Steps for Your Brand
As you prepare for the upcoming holiday season:
- Analyze your brand’s subject lines from the previous holiday season to see how your themes compared to our averages in terms of usage and performance. Zeta’s Professional Services team can help with this analysis.
- Make a test plan for both subject lines and sender name extensions to challenge your existing strategies.
- Set up a process for sharing in-season learnings across channels. For example, insights from your top SMS and push campaigns can inform email subject lines, while email results can shape messaging in those touchpoints.
Preparation leads to higher performance. This holiday season, experiment with underutilized strategies and give subscribers a clear reason to engage.
