How a personalized subject line affects open rates
Experiment ID: #10803
Hillsdale College
Founded in 1844, Hillsdale College is an independent liberal arts college with a student body of about 1,400. Hillsdale’s educational mission rests upon two principles: academic excellence and institutional independence. The College does not accept federal or state taxpayer subsidies for any of its operations.
Experiment Summary
Timeframe: 02/05/2019 - 02/19/2019
Hillsdale College sent out an offer for a free copy of the Constitution. They included the words “free” or “complimentary” in each subject line, but wanted to see if adding a recipient’s name to the subject line would affect open rates.
Research Question
Does a personalized subject line impact open rates?
Design
C: Static subject line
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) ) )
Results
| Treatment Name | Open Rate | Relative Difference | Confidence | |
|---|---|---|---|---|
| C: | Static subject line | 11.5% | ||
| T1: | Personalized subject line | 14.6% | 27.5% | 100.0% |
This experiment has a required sample size of 874 in order to be valid. Since the experiment had a total sample size of 182,541, and the level of confidence is above 95% the experiment results are valid.
Flux Metrics Affected
The Flux Metrics analyze the three primary metrics that affect revenue (traffic, conversion rate, and average gift). This experiment produced the following results:
27.5% increase in traffic
× 0% increase in conversion rate
× 0% increase in average gift
Key Learnings
The email with the personalized subject line received 27.5% more open rates than the static subject line without personalization. In the future, Hillsdale should consider including more personalized subject lines on offer emails to increase open rates.