• Ariyh
  • Posts
  • The effect of [first name] in email subject lines

The effect of [first name] in email subject lines

Including the receiver’s name in an email subject line increases their attention. Open rates increased 6-23%, clicks by 7-32% and unsubscribes fell 11-17%

Topics: Messaging & Copy
For: B2C, B2B
Research date: February 2018
Universities: Stanford University & University of Chicago

New to Ariyh? This is a 3min practical summary of a scientific study 🎓 
Subscribe for $0 to get a new science-based marketing insight every week 📈

📝 Intro

What happens when you add the receiver’s name to your email’s subject line?

There are many guides (example) that suggest doing this. 

But the data they use to back up what they say is usually weak or sketchy, and certainly not peer-reviewed.

So here is the actual scientific evidence - straight out of Stanford and University of Chicago.

Let’s take a look at what really happens, and why.

📈 Recommendation

For important or valuable emails (e.g. a special discount, a product launch), include the recipient’s name in the subject line (e.g. “Thomas, it’s finally here”).

People will be more likely to open the email and pay more attention to its contents. And if the content is relevant to them they’re more likely to take action (e.g. buy, book a demo).

Do this only if the receiver won’t be surprised that you know their name (e.g. because they provided it when signing up to your newsletter).

🎓 Findings

  • Researchers experimented with the email lists of three different companies:

    • 1,111,130 emails of Mercadolibre - the largest online marketplace in Latin America

    • 5,000 emails of Stanford University’s monthly newsletter about research and executive courses

    • 68,088 emails of an anonymous company that sells courses for professional exam preparation (e.g. Chartered Financial Analyst)

  • When they added the name of the receiver to the subject line of the emails (e.g. “[Name], Learn Financial Modeling from Industry Experts.”):

    • Open rates increased by

      • Mercadolibre: +6%

      • Stanford: +23%

      • Exam prep company: +20%

    • Clickthrough rates (CTRs) increased by

      • Mercadolibre: +7%

      • Stanford: +32%

      • Exam prep company: +31% (refers to leads generated)

    • Unsubscribe rates decreased by

      • Mercadolibre: -11%

      • Stanford: Not statistically significant

      • Exam prep company: -17%

🧠 Why it works

  • Large part of what makes marketing messages effective - or not - is how much attention we pay to them.

  • When we see our name or our company’s name in an email (subject line or in the body), we pay more attention to the content of that email.

  • And when we pay more attention we’re more likely to act on the message, especially if it’s a compelling argument.

  • The researchers did not find evidence to support two other possible reasons for this effect:

    • Seeing our name makes the email stand out in our inbox

    • We subconsciously like the company more because they use our name

💻 Brought to you by Storyblok

Want a faster, more effective way to run your website?

Try Storyblok - the next generation headless CMS:

  • Edit your website as you browse it

  • Launch new landing or product pages in minutes

  • Create content once, publish across all your channels

Try it out yourself for free - no credit card required.


  • The effect works when people are not surprised that the sender knows their name - which is usually the case in email marketing. However, it may backfire in other channels where people don’t expect the advertiser to know their name.

  • People may react negatively in markets that are particularly privacy-sensitive, such as Germany. This was not tested.

  • The researchers did not analyze the long-term effects of the technique. Because people pay more attention, they’re also more likely to remember the message for longer, which should have positive effects down the line.

  • This research does not apply to the personalization of useful information (e.g. personalized offers based on people’s location, previous purchases, etc.). The benefits, and downsides, or those types of personalizations are driven by different processes.

🏢 Companies using this

  • Most companies that collect their email subscribers’ names occasionally personalize their emails’ body or subject lines with the receivers’ names.

⚡ Steps to implement

  • Collect your email subscribers’ names when they sign up.

  • Include their name in the subject line of your email in ways that fit naturally. For example:

    • [Name], here’s an offer for you

    • Hey [name], I think you’ll like the new [Product name]

    • Haven’t seen you in a while [name], here’s what you missed

  • Use the technique occasionally, when you want readers to pay special attention, not always. Otherwise you risk diluting the effect.

🔍 Study type

Field experiments (on almost 1.2 million email subscribers from three different companies)

📖 Research

🏫 Researchers

Remember: This is a scientific discovery. In the future it will probably be better understood and could even be proven wrong (that’s how science works). It may also not be generalizable to your situation. If it’s a risky change, always test it on a small scale before rolling it out widely.

🎓 Found this insight useful?