Link your Microsoft account so the events you already have block your availability, and every new booking lands in your Outlook calendar without you copying it across.
7 min read
Updated September 2026
Integrations
In short
Go to Connected Calendars, select Connect on the Office 365 card, and approve access on Microsoft's own screen. That is the whole setup.
From then on your Outlook events block your availability, and every booking you take is added to your calendar.
Overview
What it does
Connecting Office 365 does two separate jobs, and it is worth keeping them apart in your head.
Your Outlook events→block your free slots A new TimelyDo booking→added to your Outlook calendar
The first job stops people booking over something you are already doing. The second saves you copying bookings across by hand, and means Outlook stays the one place you look.
Nobody sees what your events are. Your booking page shows which times are free and nothing else. Subjects, guests and descriptions never reach the person booking with you.
Which accounts work
Personal Microsoft accounts and Microsoft 365 work or school accounts both connect the same way.
outlook.comlive.comhotmailMicrosoft 365 work or school
One thing differs between the two. On a personal account Microsoft reports some details, such as whether a guest accepted, less completely than it does on a work account. See what differs from Google below.
Select Connect on the Office 365 card. A short overlay appears while your browser is handed over to Microsoft.
3
Approve access on Microsoft
Sign in if you are not already and approve what TimelyDo asks for. This happens on Microsoft's own page, so your password is never typed into TimelyDo.
4
You are back, and it is on
Microsoft returns you to TimelyDo and the account appears in your list with its email address. The first sync starts straight away.
Choosing a colour
Each connected calendar has a colour picker with 11 colours. Events from Outlook appear in the colour you choose on your TimelyDo calendar, so you can tell them apart from Google events and from TimelyDo bookings at a glance.
Everyday use
What blocks your time and what does not
Not every entry in a calendar means you are busy, so TimelyDo follows the same rules Outlook itself does.
Event
Blocks your time
Why
An ordinary event
Yes
You are busy, so the slot disappears from your booking page
An all day event
Yes
Covers the whole day
An invitation you declined
No
You said you are not going, so the time is yours again
An event you set to Free
No
Outlook treats it as available, and so do we
A cancelled event
No
It is not happening
This gives you a simple way to keep a slot bookable while still keeping a note in your calendar. Set the event's availability to Free in Outlook and it stops blocking, without you deleting anything.
Bookings on your calendar
When somebody books, TimelyDo adds the booking to the calendar chosen for that event type. You pick that calendar in the event editor, under Add to calendar, so different event types can write to different calendars.
The person who booked is added as a guest, so the event shows up for them too. If the booking is later cancelled, the event is removed from your calendar again.
Your TimelyDo calendar
Your Outlook events sit alongside your TimelyDo bookings on the calendar page, in the colour you picked, marked with the Outlook logo so you know where they came from. Select any event to open it and you get the time, the location, the guests, the description with its formatting intact, and a link to open the event in Outlook.
The panel also names the calendar the event came from, with the provider logo beside it. Useful when you have both a Google account and an Outlook account connected and want to know which one an event belongs to.
What differs from Google Calendar
Blocking your availability and writing bookings back work the same for both providers. A few things do not, and we would rather you knew up front than found out by trying.
Feature
Google
Office 365
Blocks your availability
Yes
Yes
Bookings written back
Yes
Yes
Answer an invitation from TimelyDo
Yes
Not yet
Drag an event to a new time
Yes
Not yet
Additional calendars on the account
Yes
Main calendar only
Guest replies on personal accounts
Microsoft does not always pass them on
Worth knowing
On a personal Outlook account, Microsoft often does not report whether a guest has accepted an invitation through the connection TimelyDo uses, even though Outlook itself shows the answer on screen. When that happens we show no reply against the guest rather than guessing at one, because claiming somebody has not answered when they have would be worse than saying nothing.
What to do
Open the event in Outlook to see the real answers. Work and school accounts usually report replies normally.
Managing
Keeping it in step
Microsoft tells us as soon as something on your calendar changes, so a new or moved event normally reaches TimelyDo within seconds. The connection that carries those notices expires on Microsoft's side after about a week, so TimelyDo renews it for you on a schedule and repairs it if it ever drops.
Each sync covers about a month back and a year ahead, which is the whole window your booking page can be booked in. The row shows when it was last synced, and the Sync button forces a fresh check whenever you want one.
Pausing a calendar
The Active toggle on each row turns a calendar off without disconnecting it. While it is off, its events stop blocking your availability. Turn it back on and everything resumes, with no need to approve access again.
Disconnecting
Select Disconnect on the row and confirm. Disconnecting does more than unlink the account, so it is worth knowing what changes:
Copies of your events
Removed from TimelyDo, so they stop blocking your availability
Bookings already made
Stay in TimelyDo exactly as they are
Event types writing to it
Fall back to no calendar, so new bookings are no longer added anywhere
Check your event types after disconnecting. Any that added bookings to this calendar will no longer do so. If you only want to stop it blocking your time, use the Active toggle instead.
Help
Troubleshooting
TimelyDo says it lost access
Reconnect from the same page
Microsoft withdraws access when you change your password, or when TimelyDo is removed from the apps listed in your Microsoft account. Syncing stops and we email you, because otherwise your availability would quietly go stale. Open Connected Calendars and connect the account again. Your event types keep pointing at it.
Some events are missing
Check the calendar and the window
Two things to check. Only the main calendar of the account syncs today, so an event on another Outlook calendar will not appear. And each sync covers about a month back and a year ahead, so something further out than that is not carried across. If neither applies, press Sync to force a fresh check.
A guest shows no reply but they accepted
A limit of personal Outlook accounts
Microsoft does not always pass a guest's answer through on personal accounts. Outlook shows it, but the connection TimelyDo reads does not carry it, so we leave the reply blank instead of inventing one. Open the event in Outlook for the real answer.
I cannot move an Office 365 event
Rescheduling is not supported yet
Office 365 events are shown and they block your time, but dragging one to a new time is not supported yet. Move it in Outlook and the new time reaches TimelyDo on the next sync, usually within seconds.
Frequently asked
Q
Which Microsoft accounts work?
Personal accounts on outlook.com, live.com and hotmail, and Microsoft 365 work or school accounts. You connect them the same way.
Q
Why does a guest still show as no reply when they accepted?
On personal Outlook accounts Microsoft does not always report a guest's answer through the connection TimelyDo uses, even though Outlook shows it. We show no reply rather than guessing. Open the event in Outlook to see the real answer.
Q
Can I answer an invitation from TimelyDo?
Not yet for Office 365 events. Answer in Outlook and the change reaches TimelyDo on the next sync. Answering from TimelyDo works for Google events today.
Q
Can I drag an Office 365 event to a new time?
Not yet. Office 365 events are shown and they block your time, but rescheduling them has to be done in Outlook for now.
Q
Do my other Outlook calendars sync?
Only the main calendar of the account syncs today. Additional calendars inside the same Outlook account are not picked up yet.
Q
How far ahead does it sync?
About a month back and a year ahead. That covers the whole window your booking page can be booked in.
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