Emails with subject lines that included the word "please" increased federal employees responses to a workplace survey

Front of building

Front of building

What was the challenge?

GSA’s Public Buildings Service (PBS) owns or leases over 9,600 assets, with more than 370 million square feet of space for over one million federal employees. Each year, PBS sends Federal employees the Tenant Satisfaction Survey (TSS), the results of which inform the Federal facilities strategy.

What was the program change?

Small details, such as the framing or timing of an email, can matter more than might be expected. Varying subject line wording (e.g., including “please”) of workplace email requests can affect email open and click-through rates. Using this research, we redesigned and reconfigured the TSS to assess what subject lines, as well as what day of the week on which the email is sent, resulted in the highest open and click-through rates.

How did the evaluation work?

An announcement email was sent to two randomly assigned groups of approximately 11,500 Federal employees three times a day for a week—at 9:00 a.m., 12:30 p.m., and 4:00 p.m., ET. In addition to time-of-day and day-of-week variation, aspects of the subject line were also varied (e.g., action statement, use of please, and use of exclamation point), testing paired permutations against each other.

What was the impact?

Sending emails near lunchtime on Tuesdays and Wednesdays resulted in higher responses than other days and times. Also, results indicated that including “please” in subject lines increased response rates, while adding an exclamation point reduced response rates.





Project Type

Impact evaluation of program change


General Services Administration


Government Operations

View Abstract (PDF)