You're a tutor based in Warsaw. Your student is in San Francisco. You agree on a weekly lesson: Tuesdays at 6pm.
For three months, it works perfectly. Then one Tuesday, you show up and they don't. You wait fifteen minutes, send a message, get no reply. An hour later they respond: "I was there at 6! Where were you?"
You were both right. Daylight Saving Time had changed in the US, but not in Europe yet. The lesson that was 6pm for both of you was now 6pm for one and 7pm for the other.
No one made a mistake. The system made a mistake.
That student rescheduled once, then twice, then just... stopped booking.
The Invisible Problem
On platforms like Preply or italki, you never think about timezones. The platform handles conversion invisibly. You see your time, they see theirs, and it just works.
When you go independent, you become the timezone converter. And you're going to get it wrong. Not because you're careless—because the problem is genuinely hard.
Consider: DST starts on the second Sunday of March in the US, but the last Sunday of March in Europe. That's a 2-3 week window where every single US-Europe lesson is off by an hour, unless someone catches it manually.
Australia's DST moves in the opposite direction—they spring forward when the northern hemisphere falls back. If you have students in both Sydney and Chicago, there's a period every year where your schedule shifts by two hours relative to one of them.
This isn't an edge case. If you teach students internationally, this will happen to you multiple times per year.
"Let's Do 9pm"
Even without DST, the daily friction adds up.
A student messages: "Can we move to 9pm this week?"
Whose 9pm? You check their profile—you noted their city somewhere, hopefully—and calculate the offset. Except you're not sure if you noted it in summer or winter. And was that their home city or where they said they were traveling?
You take your best guess and reply. They confirm. The lesson happens... or it doesn't.
This is the kind of low-grade cognitive load that makes tutoring feel harder than it should be. Every single scheduling message requires you to do math, or open a timezone converter, or dig through notes. It's never automatic.
And when you're managing ten, fifteen, twenty students across four or five timezones, the math becomes a full-time background process.
The Quiet Churn
Here's the thing about timezone mistakes: students rarely complain.
They just leave.
A missed lesson feels like your fault to the student, even when it isn't. They showed up, you didn't (from their perspective). They're not going to email you to argue about DST—they're going to find a tutor who "shows up."
You might not even know you lost them to a timezone error. It looks like normal churn. They just stopped booking. Maybe they got busy, you think. Maybe they lost interest.
Maybe you told them 3pm and they didn't know which 3pm you meant.
What Actually Works
A few things help:
Always confirm in their timezone. Don't say "Tuesday at 6pm"—say "Tuesday at 6pm your time (San Francisco)." Yes, every time. Even with regulars. The two seconds it takes to type that saves hours of confusion.
Pick a reference timezone for yourself. Some tutors work exclusively in UTC and convert everything. It's a bit robotic, but it means you're never confused about what your schedule says.
Watch the DST calendar. Seriously. Know when your major student regions change their clocks, and proactively message those students the week before. "Just a heads up—US clocks change this Sunday. Our lesson stays at 6pm your time, which means it'll be an hour earlier for me."
Use a tool that does this automatically. This is the real answer. You shouldn't be doing timezone math in your head. You shouldn't be maintaining a spreadsheet of student cities. The technology to solve this has existed for decades—it just needs to be packaged in a way that works for tutors.
This Is Why We Built SandGlass
Timezone conversion is one of the core problems SandGlass solves.
Here's how it works: you set your availability once, in your own timezone. When a student looks at your schedule, they see it in their local time—automatically converted, DST-aware, no math required.
You see "Tuesday 6pm." They see "Tuesday 9am." It's the same moment. Neither of you has to think about it.
When clocks change, the conversion updates. When a student messages you, their timezone is right there in their profile. When you look at your week, every lesson shows both times—yours and theirs—so you never have to wonder.
It's not a feature we added because it seemed cool. It's a feature we added because timezone chaos is one of the top reasons independent tutors burn out or lose students. And it's completely fixable.
Try SandGlass free — no commission, no percentage fees, just a flat $12/month after the free tier.
This is part of our series on building a sustainable independent tutoring practice. Previously: The True Cost of Preply's 33% Commission.