The original genius of email was that the sender could launch her missive at a time convenient for her. The recipient could read it at a time convenient for him. Both parties could compose their thoughts without the immediate time pressure that being on the phone requires.

So much for that.

Thanks to smartphones in our pockets, email is always with us. When it comes to email response times, “The expectation has gotten worse because of this availability at your fingertips,” says Aye Moah, chief of product and co-founder of Boomerang, which makes email productivity software. When people can respond immediately, it raises the question of exactly how long it’s okay to wait to respond to an email.

The bad news from analyses of millions of emails is that people do expect swifter responses. The good news, however, is that you can manage this expectation, and buy yourself time if you need to.

“Fifty percent of responses are sent within two hours, and according to one study, the most common email response time is two minutes.”

Doing Your Job Means Disappointing Someone

This starts to become difficult to achieve. You can easily be driving somewhere for an hour during the day, or presenting in a meeting and hence unable to respond. Even if you are available, responding to more complicated requests might take several minutes, which means you could not respond to too many of these within an hour. Simply doing your job means you will be disappointing someone.

The good news, however, is that this realization is liberating. You simply cannot please everyone, and hence you don’t have to try to please everyone. In an era of immediate responses, “It’s harder for us to hold back and say, ‘I will respond when it is appropriate for me and when I have time,’” says Moah, but “I think there is a movement to hold back the tide.”

“In an era of immediate responses, it’s harder for us to say, ‘I will respond when it is appropriate for me and when I have time.’”