Email Study Results

A recent study by USC Viterbi School of Engineering researchers found that speed of email responses depend on a variety of factors including age, platform, volume, and timing.

The paper, "Evolutions of Conversations in the Age of Email Overload," was presented at the World Wide Web Conference. The paper is the largest study of email to date, measuring how the volume of incoming email affects behaviors of recipients and the length of time it takes them to reply to emails. The study was conducted in accordance with privacy standards: individuals opted in to the study, the data was anonymized, and the emails were not read by humans.

The researchers said ninety percent of people respond within a day or two of receiving an email to which they plan to respond. Half of responders will respond in just under an hour.

Age is also an indicator for email response time. Younger people reply faster, but write shorter replies. Teens were the quickest, with an email response time average of 13 minutes. Young adults aged 20-35 years responded on average of 16 minutes of receiving an email. 35 to 50 years tended to respond in 24 minutes, on average. Those over 51 years of age, on average took 47 minutes to respond.

Women typically respond four minutes longer than an email response from a man. The platform also plays a critical role: If someone is working from a laptop, on average it will take them almost twice as long to respond than if using a mobile phone.

Emails with only five words are the most common. More than half the email replies are less than 43 words, and only 30 percent of emails are longer than 100 words.

Younger users can cope with the increased email load more than older email users. When younger users become more overloaded they tend to send shorter and faster replies to cope with the increased load. On the other hand, older people respond to an increased load of emails by replying to a smaller fraction of emails.

It is no surprise that people are more active on email during the day than at night. Emails on weekends get shorter replies than weekdays. If you want a longer and perhaps more thoughtful reply, email someone in the morning. The researchers found that emails sent in the morning tend to get longer replies than those in the afternoon.