How Much Time Do Employees Spend on Slack? The Real Daily Benchmark

How much time do employees spend on Slack? About 90 minutes of active use per workday — and roughly nine hours of being connected to it. That gap, between the 90 minutes people are actually typing, reading, and clicking in Slack, and the nine hours the app sits open in their dock or on their phone, is where the modern workday quietly goes to die. Leaders who track project progress through Slack channels tend to carry an ambient, never-off awareness of it, and the data shows they are not imagining the pull.

Before the numbers, notice the pattern every manager recognizes instantly: a question is asked in a channel at 9:15 AM, three people reply with partial answers, a fourth drops a file, and by 11 AM nobody can reconstruct what was actually decided. This is not a Slack failure — it is a usage pattern. Slack became the default system of record for project status without anyone deciding it should be, and the time cost shows up in every benchmark. The benchmark comes from Slack itself: among paid customers, users spend more than nine hours per workday connected to the service, including about 90 minutes of active use. That is the official number, published by Slack in 2019 and still the most-cited figure in every 2026 statistics roundup. It has aged well because the underlying behavior has not changed — Slack has only become more central to how teams operate.

The 90-minute benchmark: Slack's own number

Slack's official blog has stated that paid-customer users spend about 90 minutes per workday actively using Slack, on top of being connected for more than nine hours. That active time adds up to more than five billion actions a week across the platform — sending messages, reading threads, commenting on files, running searches, and interacting with apps.

The 90-minute figure dates to September 2019, when Slack reported 12 million daily active users. It remains the anchor number because Slack has never published a lower or higher replacement, and every subsequent roundup of Slack statistics repeats it. What has changed is the denominator: by 2025, DemandSage estimated Slack's daily active users at 47.2 million, up from 38.8 million in 2024. More people, same per-person habit — the aggregate time drain has roughly quadrupled since 2019. For comparison, the same coordination tax shows up on other surfaces: the average employee also spends a meaningful chunk of the week in email and in meetings, as we broke down in the email time benchmark and the meeting hours benchmark.

For the team lead, the honest reading of 90 minutes is conservative. The benchmark measures active interaction, not the passive cost. Every minute Slack is open in the background is a minute of divided attention, and the platform itself reports users stay connected for nine hours — more than the length of a standard workday. The active number understates the real footprint.

Nine hours connected, 90 minutes active: the gap

The nine-hours-connected figure is the more alarming half of the benchmark, because it describes the default state of the worker, not their deliberate choice. Slack reports paid users stay signed in for more than nine hours per workday through at least one device. A laptop during the day, a phone on the commute and after dinner — the channel is simply available, and availability is not free.

RescueTime's analysis of 50,000-plus knowledge workers found the average person checks in with communication tools every six minutes during the workday. In an eight-hour day, that is roughly 80 check-ins — most of them quick, most of them harmless on their own, and none of them free. Each glance costs a slice of attention that never fully returns to the task at hand.

The connected-versus-active gap also explains why Slack feels so much more expensive than its 90-minute headline suggests. A worker who is connected for nine hours but active for 90 minutes is not ignoring Slack; they are half-watching it. They are monitoring channels while writing, waiting for the ping while reading, and pre-emptively checking whether an update has landed. That ambient vigilance is the hidden second job of the Slack-native workplace.

What Slack time actually costs

The dollar figure attached to this behavior is striking. RescueTime's research into the cost of Slack and email puts the price of time spent on email and instant messaging tools at $28,209 per employee per year in lost productivity. For a 50-person team, that is a $1.4 million line item that never appears on any budget — entirely consumed by communication overhead. The same dataset found that most knowledge workers "check in" with communication tools every six minutes, which means a Slack-heavy day is not one long focus block with interruptions, but roughly 80 small attention breaks that each carry a restart cost.

The per-day message volume gives the scale. More than 1.5 billion messages are sent on Slack every day, and roughly three-quarters of users send messages through public channels rather than private DMs. That is a lot of broadcast, and very little of it is about shipping. In practice, most of what flows through channels is coordination chatter: statuses, questions, confirmations, and the endless "any update on this?" pings that managers send when they have lost the thread of a project.

The growth trajectory says this is not getting better on its own. Slack grew from about 12 million daily active users in 2019 to an estimated 47.2 million in 2025, and the message volume grew with it. Every Slack statistics roundup published in 2026 repeats the same 90-minute active-use figure because it is still the best number anyone has — the platform scaled, the per-person habit stayed, and the coordination tax scaled right along with it.

Nine hours connected, 90 minutes active, $28,209 per employee per year, and a check-in every six minutes. The tool became the work.

None of this means Slack is bad software. It is exceptionally good at what it does, which is precisely the problem: the easier it is to ask, the more people ask. The tool that eliminated email chains became the place where project context accumulates in fragments — a decision in one thread, a status in another, a stakeholder question in a third — and every fragment carries a small tax of attention. We covered the mechanics of how project updates get lost in Slack and what it costs teams who keep chasing them down channels.

What good looks like

The teams that keep Slack useful treat it as a switch, not a state. They set explicit response-time norms, protect deep-work blocks, and — most importantly — stop using chat as the system of record for project status. Instead of asking "any update?" in a channel and waiting for three people to reconstruct the story from memory, they give updates a single visible home.

That home is what Asa.Team's Project Intelligence is built to be: it surfaces project updates from Slack, Teams, Telegram, and WhatsApp and pulls them into one place, so a leader does not have to stay connected for nine hours or check in every six minutes to know what is happening. The status comes to you, assembled from the chatter that already exists — no new rituals, no more chasing threads.

Slack becomes what it was supposed to be: a place to talk, not a place to keep the record. The 90-minute benchmark does not have to be a floor; teams that move status out of chat recover more of their day than they expect.

Frequently Asked Questions

How much time does the average employee spend on Slack per day? About 90 minutes of active use, per Slack's own data, plus roughly nine hours of connected time. Active use means reading, writing, and clicking; connected means the app is signed in and available.

Is 90 minutes a day on Slack a lot? For a single tool, yes. Ninety minutes is roughly 19% of an eight-hour day spent actively inside one messaging app — before accounting for the attention cost of being connected for nine hours and checking in every six minutes.

How many messages are sent on Slack per day? More than 1.5 billion messages per day, and about five billion weekly actions including message reads, file comments, searches, and app interactions.

Does Slack save time compared to email? Slack has claimed it reduces email by 32% and meetings by 27% among its users. The trade-off is that the time saved on email reappears as Slack time — the same coordination cost, moved to a faster channel.

The 90 minutes is a symptom, not the diagnosis

Slack time is not waste by itself; it is the visible surface of a deeper problem. The reason teams spend 90 minutes a day actively in Slack is that their project status lives there — scattered across threads, duplicated between channels and DMs, and only legible to the person who has been following along since the beginning. That is not a communication culture problem. It is a project-intelligence problem.

The question worth asking is not "how do we get people off Slack?" It is "why does knowing the state of our projects require anyone to be on Slack at all?" When the answer to that question changes, the 90 minutes shrink on their own — and the nine hours of connected time stop feeling like a job requirement.