If the pandemic has revealed anything about work life , it’s that work and life are melded like never before: morning staff meetings streamed from the breakfast table; in-person presentations before school pickup; and evenings of quiet concentration whenever the opportunity avails.

Findings from Microsoft and its researchers suggest that the 9-to-5 workday is fading in an age of remote and hybrid work and more flexible hours. That pattern was first spotted early in the pandemic, when Microsoft Teams chats outside the typical workday increased more than in any other time segment, particularly between 6 p.m. and 8 p.m.

Newer data suggests the trend is here to stay. Traditionally, knowledge workers had two productivity peaks in their workday: before lunch and after lunch. But when the pandemic sent so many people into work-from-home mode, a third peak emerged for some in the hours before bedtime. Microsoft researchers have begun referring to this phenomenon as a “triple peak day.”

“Having your kids at home, having no breaks to eat or exercise, we see that one of the ways to cope is to take a break, eat dinner, and then spend time in the evening actually getting things done,” says Mary Czerwinski, research manager, human understanding and empathy, at Microsoft Research. Parents who tend to their children in the afternoon make up for that time by working in the evening. Others optimize newfound work-from-anywhere flexibility by varying their hours. Some just require the extra breathing room at night, away from pings and business calls, to really focus.

“It raises the question, ‘Is this about flexibility, or is it about work encroaching on someone’s personal hours?’ ”

Shamsi Iqbal, Microsoft Research and Viva Insights

Now that some people have grown accustomed to the “triple peak day,” what happens in the transition to hybrid work? Should there be new ground rules and guidelines that differ from other parts of the day? How can managers support team members who choose to work non-traditional hours? And what are the implications for wellbeing when every spare hour is potentially “on the clock”?

“This [third] peak is different from the other two peaks because it raises the question, ‘Is this about flexibility, or is it about work encroaching on someone’s personal hours?’ ” asks Shamsi Iqbal, principal researcher on productivity and intelligence at Microsoft Research and Microsoft Viva Insights.

What the data shows

Any way you slice it, the boundaries between “office hours” and everything else became thinner this past year and a half. The average Teams user now sends 42 percent more chats per person after hours, according to Microsoft Work Trend Index findings.

When Czerwinski and her team studied the activities of some Microsoft employees this summer, they noticed that about 30 percent of them had an evening spike in work, as measured in keyboard usage. The timing and amplitude varied from person to person, but it was less intense than the two work peaks earlier in the day.

The researchers continue to study the data, and it’s not yet clear exactly what caused the uptick for some employees—whether, for example, it was related to daytime childcare responsibilities or jobs requiring cross-country collaboration. But the findings bear out a more general trend: In our current era of hybrid work, there is no one size fits all. Some people stick to traditional office hours; others don’t. In where, how, and when they work, people are looking for flexibility.

“Now with the triple peak, people have the ability to do what they need to do in the moment and still have time to work later on. That’s super important as far as reducing stress levels,” Czerwinski says.

In Practice

What a triple peak day looks like

This graph represents the working patterns of study subjects as a whole.
Illustration by Valerio Pellegrini

Life after 9 to 5

While many see the benefits of flexible hours, there are downsides too. Some people relish the chance to slip in a mid-afternoon workout between meetings and make up for that time by working after dinner, while others mourn the loss of a defined 9-to-5 workday and the feeling of freedom they once had after leaving the office for the evening.

“The third peak should be an available option for people who need it, but the challenge moving forward is, ‘How can we make sure people are not working 24/7?’ ” Iqbal says. “If people are working all three peaks, that’s a recipe for early burnout.” Breaks are essential to productivity and wellbeing, and the research backs that up.

Working late certainly isn’t new. The English phrase “burning the midnight oil” dates back to 1635 as a rewording of “elucubrate,” meaning to work by the side of a candle. Autonomous workers of all stripes—consultants, academics, writers, programmers—have long set their own hours according to personal preference and workload.

What’s different now is the commingling of home and office responsibilities across nearly every sector of the workforce. “More than ever, people are taking on additional day duties that they didn’t have before, whether it’s caring for kids and helping with schooling or being a caretaker to another family member,” says Gloria Mark, a professor in the Department of Informatics at the University of California, Irvine, and a visiting researcher at Microsoft since 2012. “This is a new piece of the puzzle that’s pushing a lot of people to work later,” Mark says.

Likewise, teams working across different time zones often schedule meetings during non-traditional hours to accommodate core collaborators. Iqbal uses the example of someone in the Pacific Northwest working with team members in India who are 12 hours and 30 minutes ahead. As our tools make these types of collaborations more practical and efficient, “we’re seeing our productivity peaks move around,” she says. “With distributed teams, you often need to shift focused work time to make the most of it.” To avoid too many meetings at unconventional hours, companies can also tap more asynchronous forms of communication—for example, doing status updates in a Microsoft Teams channel instead of in a video conference.

Empathy, communication, and personal choice

The collaborative realm is one area where new guidelines might help prevent triple peak work hours from becoming a horror show of overextension. A key to mitigating the “always on” mentality is to have managers work with teams on explicit norms. It’s also essential to check in with people who may feel like they need to work round the clock to keep up. Different workers have different needs and challenges, many of which go unseen. Empathy and communication are essential.

“Workers are not islands,” Iqbal says. “Right now you cannot assume that everyone on your team is going to be available during the 9-to-5 timeframe, or that others will want to collaborate when you’re working outside regular business hours.” Such expectations die hard. Iqbal’s extensive research on email and other messaging applications reveals that most people feel the need to respond to digital interruptions the moment they land. “I think we need to reset the expectation and realize that most information, unless it’s urgent, can wait for a reply,” she says.

As employees redesign their workdays again in the shift to hybrid, it’s important that organizations support them through times of change.

Scheduling options—currently in Outlook and coming soon to Microsoft Teams —allow users to arrange for after-hours messages to hit inboxes only when working hours resume. These pauses reduce stress for both sender and recipient. “People often send emails at odd hours because they don’t want to lose the thought and they want it captured, but it doesn’t necessarily have to arrive at the recipient’s end right away,” Iqbal says. “Delaying delivery of that email means that we can get the best of both worlds—capturing the thought so that it doesn’t get lost, and making sure that the recipient gets it at a time that is more convenient for them.”

Features like these work best when a team agrees on how to use them, says Colette Stallbaumer, general manager of Microsoft 365 and Future of Work at Microsoft. Stallbaumer was initially reluctant when her team decided to abstain from sending emails after 6 p.m. and on weekends. But after a few weeks without afterhours pings, she began to appreciate the quiet time to either focus or unwind. “When everyone does it together, it really does make a difference,” Stallbaumer says.

Mark, meanwhile, sees advantages in using triple peak periods for more autonomous types of work. Rather than engaging in what she calls “tightly coupled” work in which quick decisions and group input are essential (think: brainstorming around a whiteboard), she sees value in using the “5 to 9” for “loosely coupled” activity: a report in which everyone is responsible for a different section, solo writing projects, or a software program with separate elements to develop. “Rather than extending everyone’s work into the evening, you can let it work for those whose peak performance hits in that timeframe,” Mark says. “So a coder can go do her work independently and then come back the next morning and see if the whole thing works once everyone is together.”

The focus now isn’t so much on when people are working, or even where, but rather on how people can work better. “Every single person on a team has a different context within which they’re trying to be productive,” Czerwinski says. “You have to give everyone space to do it on their terms. Some of them might have babies, some of them have teenagers, some of them might not have kids, but they work best at night. Some are in another time zone and are asynchronous. The key is, they can all be productive, but they have to do it in a way and at a time that’s personalized. It’s all over the place in terms of how you can be your original self at work and really contribute.”

As employees redesign their workdays again in the shift to hybrid, it’s important that organizations support them through times of change. Managers need to model sustainable working practices—and offer coaching and regular check-ins that show they care. They need to make sure people are getting the breaks they need to recharge and adopting patterns that feel healthy and rewarding. If someone is regularly logging back on after dinner, it should be for one reason: because they work and live better that way.