“Post at 9am” is half an instruction. The other half is whose 9am. Most wrong-hour posts are not typos in the caption. They are a correct time in the wrong zone, noticed after the post has gone out.
This guide is about the decisions, not the buttons. If you want the short tour of the scheduling screen, the Scheduling feature page has it. Here we work through one realistic case, then the traps around it.
A worked example: Karachi to New York
Sana runs social media from Karachi for a bakery in New York. The bakery’s customers check Instagram over breakfast, so she wants every post out at 8:00 a.m. New York time for the next two weeks. That stretch includes Sunday 1 November 2026, the day the United States moves its clocks back one hour. Pakistan does not change its clocks at all.
Here is what that means in her own time:
- Until Saturday 31 October, New York is on daylight time, so 8:00 a.m. there is 5:00 p.m. in Karachi.
- From Sunday 1 November, New York is on standard time, so 8:00 a.m. there is 6:00 p.m. in Karachi.
Same intention, two different Karachi hours. If Sana did the arithmetic herself and entered 17:00 for every post, everything after the change would reach New York at 7:00 a.m. An hour early, every day, and no error message to tell her.
So she does not do the arithmetic. In the composer she sets the Timezone dropdown to New York first, then types 08:00 as the time. The post is now an 8:00 a.m. New York post, and the change on 1 November is handled for her. Before saving she reads the date back once, because the two weeks cross the change.
Her calendar still shows 5:00 p.m. for the early posts and 6:00 p.m. for the later ones, because the calendar draws times on your own device’s clock. That is expected. Open any post to see the zone it was set in.
Which zone should a post use?
There are really three candidates, and each answers a different question.
- The audience’s zone. Use this when the post should land at a particular moment of their day: breakfast, a lunch break, the evening commute. It is the right answer most of the time, and it is what keeps the post steady through their daylight saving changes.
- Your own zone. Use this when the timing is about you rather than them: a live session you will be hosting, an office-hours reminder, a “back from holiday” post.
- UTC. Use this for something tied to a single global moment, such as a launch announced at a fixed time for everyone. It never shifts, but it will not follow anyone’s local clock.
If a post has two audiences, it needs two posts. One zone cannot be breakfast in both New York and Singapore. Schedule a copy for each and set each to its own zone. The Suggested times row under the date and time fields shows peak hours for the channels you picked, read in the zone you chose, so set the zone first and look at the suggestions after.
Mistakes that move a post by hours
Leaving the default. A new post starts with the zone your browser reports, which is where your device thinks it is. Travelling, using a VPN or borrowing a laptop can make that something other than where you work. Check the dropdown before you queue anything.
Expecting the dropdown to convert. Changing the zone keeps the clock time and re-reads it in the new zone. A post at 09:00 in London becomes 09:00 in Los Angeles, not the Pacific equivalent of London’s 9. That suits the usual intent, “9am for them”, but it surprises people who expected a conversion. If you want one, work out the time and enter it.
Entering the time in your zone and the zone as theirs. This is the Karachi mistake in reverse. If you typed 17:00 because that is 8:00 a.m. in New York, and then set the zone to New York, you have scheduled 5:00 p.m. in New York. Pick one frame of reference: either type the time in the zone you selected, or select your own zone and do the conversion. Mixing them is how an 8am post becomes a 5pm post.
Assuming both sides change on the same day. The United States and Europe move their clocks on different weekends, so for about a week the gap between London and New York is an hour smaller than usual. If you schedule by subtracting hours in your head, those are the days you get it wrong. Setting the audience’s zone avoids the sum entirely.
Scheduling into the hour that does not exist. When clocks spring forward, 02:30 never happens that night. A post set for it goes out at 03:30, the way the clocks themselves move, and not an hour earlier. If the exact minute matters on a change night, pick a time well clear of the gap.
A quick check before you queue
- Does the Timezone dropdown show where your audience is, not where your laptop is?
- Did you type the time in that zone’s clock?
- Does the date range cross a clock change in their country? If so, open one post on each side and read its time back.
- For a global audience, is there one post per region rather than one compromise time?
Repeat schedules and the daily limit
A repeat schedule has its own Time and Timezone fields in the Repeat Schedule panel. A weekly post at 9:00 in Chicago stays at 9:00 Chicago time all year, even though the gap to UTC changes. If a schedule has no zone of its own, it uses the one on the post it was created from. See recurring social media posts for what repeats are good for.
The daily limit on scheduled posts follows the post’s zone too. A “day” means the calendar day in that zone, so two posts a few minutes apart in UTC can fall on different days for a Sydney audience. The limit is Free: 3, Pro: 30, Business: 100 scheduled posts per day. You find out at the moment you try to schedule one past it.
If you use Add to queue instead of choosing a time, the slot window is 9am to 8pm in the post’s zone. Set the zone to your audience first and the slots land inside their waking hours.
In the API
scheduledAt names one exact moment, so send it with an offset or as UTC, for example 2026-11-02T13:00:00Z. timezone is an IANA zone name such as America/New_York, optional and defaulting to UTC, and an invalid name is rejected. The moment comes from scheduledAt. The zone records what the post belongs to, and is what the daily limit and the post’s detail view use. For “8am in New York”, work out the instant yourself and send both. The scheduling API guide has the full request shape.
When not to bother
If you and your audience are in the same place, leave the default and forget all of this. If you do not know where your audience is, a zone will not help; look at your analytics first, and the best time to post guide covers how.
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