Guide from the Subject Line Tester
Should You Use Their Name in the Subject Line?
Short answer: you can, but do not count on the name to do the work. The words that matter most are the ones about the reader's topic or problem. Here is what the research says, where it disagrees, and how to decide.
What the research says
A 2018 field experiment published in Marketing Science found that adding a first name to marketing email subjects could help. It is often quoted as proof that names always work.
A 2023 study in Marketing Letters set out to test the same idea again and did not find that first-name effect. When a newer test fails to repeat an older result, it is wise not to lean on the older result. Both studies were about marketing email, not one-to-one sales email, which is one more reason not to treat a name as a sure thing.
Why a name alone is not enough
A first name shows that you know who you are writing to. It does not show that you know anything about their work. Research on cold email personalization draws that line clearly: a researched detail tied to a problem is personalization, and a first name or company name dropped into a template is not.
Gong's research adds that the right detail depends on the reader. A senior buyer needs to see a company priority. A name or a hobby with no business challenge attached is not enough.
Based on: Woodpecker, 2026Gong Labs, 2023
When a name can make sense
A name works best when it sits next to a real topic. “Sam, renewal dates for the Denver team” (an invented example) uses the name and still says what the email is about. A name can also feel natural when you already know the person or a colleague introduced you. This is a writing practice, not a study result.
Writing practice, not a study result.
Mistakes to avoid
- Leftover placeholders, like {{first name}}, which tell the reader the email came from a template.
- A misspelled name. Check it against their own email signature or profile.
- A name plus a vague teaser, like “Sam, quick idea”, which still says nothing about the topic.
- Overly familiar openers with someone you have never met.
Writing practice, not a study result.
How the Subject Line Tester treats names
The Subject Line Tester does not give extra points for a first name, and a name next to a real topic is not marked down. It checks whether the subject says what the email is about. A subject that is only a name gets a note asking you to add the topic that matters to the reader.
Based on: Marketing Letters, 2023
See how your subject line reads
Type your subject line, with or without the name, into the Subject Line Tester. It explains in plain words whether the subject says enough about the reader's topic, and links the research behind each check. It is free, and nothing you type is stored.
Try the Subject Line TesterSources
- Marketing Science. Personalization in Email Marketing: The Role of Noninformative Advertising Content (2018). Read the source
- Marketing Letters. Personalized subject lines in email marketing (2023). Read the source
- Woodpecker. Cold Email Statistics Based on Sending Over 20M Cold Emails (2026). Read the source
- Gong Labs. 4 effective ways to boost your email reply rate and book more meetings (2023). Read the source
Advice marked as writing practice is common sense for clear email, not a study result. See where all of our guidance comes from. No statistic on this page is invented.