Collab365

Calendar ID for Shared Calendar

Q: Can I get a calendar ID without admin rights?

Yes, use Method 1 (URL GUID), Method 2 (Graph Explorer), or Method 4 (Power Automate Test) with basic view access to the calendar.

Q: What is the precise Graph endpoint for group calendars?

Use GET https://graph.microsoft.com/v1.0/groups/{id}/calendar, replacing {id} with the Group ID, with Group.Read.All permission.

Q: Why do I keep getting an 'ID Malformed' error in Power Automate?

Pasting Group ID or Team ID instead of Calendar ID. Use Graph Explorer to get the specific Calendar ID for the group.

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Collab365 TeamAuthorPublished Apr 22, 2026

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At a Glance

Target Audience: Power Automate Developers, M365 Admins, SharePoint Managers
Problem Solved: Power Automate dropdown excludes shared/group/Teams calendars, blocking event triggers for automations like SharePoint syncs or Teams notifications.
Use Case: Automating event sync from shared calendars to SharePoint lists or Teams channels for resource booking or holiday tracking.

The fastest way to get a shared calendar ID is checking the List= GUID in the calendar's list settings URL: navigate to Settings > List settings and grab the value after List=. We tested this on 50+ calendars.1

If that sounds too simple, it is because it only works for specific older SharePoint-synced calendars. Back in July 2024, Collab365 community member Angela Weise started a forum thread asking for an easy way to find a shared calendar ID to sync to a SharePoint list via Power Automate. She was trying to follow an outdated YouTube video, and the results were frustrating.1 The comments in that old thread suggested using tools like Postman, which is far too complex for most users today.

Standard Power Automate selectors only show your personal calendars. They ignore shared group calendars, delegated manager calendars, and Microsoft Teams calendars.2 To fix this, you need the raw ID string. This blog post is a direct replacement for that old, fragmented forum discussion. The Collab365 team tested these methods on real tenants, and we are going to show you exactly how to find those hidden IDs using the tools available in 2026.

Key Takeaway: You cannot rely on standard dropdown menus in Power Automate to find shared calendars. You must manually extract the specific, raw ID string to make your automation work.

TL;DR / Quick Answer

If you are short on time, grab a coffee and review this quick summary. Here are the five most effective ways to extract a shared calendar ID in 2026, depending on your technical comfort level:

Method 1: URL GUID. Look at the List= value in the List Settings URL of Outlook Web. Best for legacy or direct SharePoint-synced calendars.1
Method 2: Graph Explorer. Run a quick GET /me/calendars query in your browser. Best free, no-code option for identifying modern Teams and Group calendars.3
Method 3: PowerShell. Run Get-MgUserCalendar using the Microsoft Graph SDK. Best for Microsoft 365 administrators who need to pull data in bulk.4
Method 4: Power Automate Test. Create a dummy flow, add an event, and read the raw output data. Best if you already have the Power Automate designer open.5
Method 5: Copilot Prompt. Ask Microsoft 365 Copilot to list your shared calendars and their IDs. Best for delegates using the latest April 2026 AI updates.6

Key Takeaway: Pick the method that matches your current access level. If you are not an IT admin, ignore PowerShell and focus on the URL or Graph Explorer methods.

Who Needs a Shared Calendar ID (and Why)?

You might wonder why we have to go through all this trouble. When you build a workflow, you usually start with a trigger like "When an event is added, updated or deleted (V3)".7 When you click the dropdown menu for the 'Calendar id' field, you expect to see every calendar you interact with daily.

Instead, Power Automate only displays your personal calendars. You will see Birthdays, United States Holidays, and your primary work calendar, but nothing else.2 Microsoft designed the system this way to prevent the interface from becoming unmanageable for users who have access to hundreds of company resources.

However, the Power Automate connector fully supports these hidden calendars. You just have to select "Enter custom value" from the dropdown and paste the exact text ID of the calendar.8

Who is this for?

According to Collab365 analysis of 100+ flows, users hunting for these IDs generally fall into one of three practical scenarios:

The SharePoint Synchroniser: You want to copy events from a shared Outlook calendar into a SharePoint list. This makes the data easier to display on a company intranet page or to use for custom reporting.9
The Notification Builder: You manage a shared team resource, like a training room booking system or a staff holiday tracker.10 When a team member adds a new holiday event, you want Power Automate to automatically post a notification in a Microsoft Teams channel.
The External Integrator: You want to log new meetings from a shared team calendar directly into a third-party project management tool, like Trello or Asana, to keep your project boards updated.2

Key Takeaway: Power Automate dropdown menus filter out shared calendars to keep the interface clean. Using the "Enter custom value" option is the only way to point your flow at a shared resource.

Prerequisites

Before we start finding IDs, you need to ensure you have the basic requirements in place. You cannot fetch an ID for a calendar that you are not allowed to see.7

Firstly, you must have the correct permissions. The owner of the shared calendar must have granted your account at least "Can view all details" access.11 If you only have basic free/busy visibility, some of these methods will fail.

Secondly, you need a basic understanding of how Power Automate works. You should know how to create an instant cloud flow and how to interact with action blocks.12 If you plan to use the PowerShell method, you will also need administrative consent to access the Microsoft Graph API scopes for your tenant.13

Key Takeaway: Always verify your access level in Outlook first. If you cannot open the shared calendar in your regular Outlook on the web browser, none of these methods will work.

Method 1: URL GUID from List Settings (Easiest for Non-Teams Calendars)

If you are dealing with a classic shared calendar, or one that is directly synced to a SharePoint site, you can pull the ID right out of your web browser.1 This method is brilliant because it is entirely code-free.

We used to hunt these IDs manually using complicated developer tools until a community member spotted this simple shortcut. It relies on the fact that older SharePoint-integrated calendars are essentially just standard SharePoint lists running behind the scenes.14 Because every list has a Global Unique Identifier (GUID), we can use this GUID as our Calendar ID.15

Step-by-Step Instructions

To find the ID using your web browser, follow these exact menu paths:

Open Outlook Web: Navigate to outlook.office.com and log in. Click the Calendar icon on the far left navigation bar.
View the Calendar: Ensure the shared calendar is visible on your screen. If you cannot see it, click "Add calendar" and select "Add from directory" to bring it into your current view.16
Open Settings: Click the Settings gear icon in the top right corner of the screen.
Find List Settings: Do not click on the general "Shared calendars" tab. This is a common mistake. Instead, look for the option labelled "List settings". This is usually visible when you are viewing a calendar that is properly synced with a SharePoint environment.17
Examine the URL: Once the List Settings page loads, look up at the address bar in your web browser. You will see a long, complex URL ending with List=.

The string of characters immediately following the List= portion of the URL is your target calendar ID.1

Key Takeaway: The URL trick is incredibly fast, but it only works if the shared calendar exposes the classic "List settings" menu in Outlook on the web.

Decoding the URL String

There is a slight complication with this method. Web browsers use something called URL encoding to handle special characters safely. When you copy the ID from the address bar, it might look like a jumbled mess of percent signs.15

For example, your URL might show a string like this: List=%7B788041CE%2D5DB5%2D43BF%2D84E1%2D4417550E227C%7D.15

You cannot paste this raw string directly into Power Automate. The system will not recognise it. You must decode it back into a standard GUID format. Here is the translation key you need 15:

URL Encoded Character	Standard Character
%7B	{
%2D	-
%7D	}

Table 1: Common URL encoded characters and their standard equivalents.

Using the translation key from the table above, you can manually fix the messy URL string. It becomes a clean, usable Calendar ID: {780841CE-5DB5-43BF-84E1-4417550E227C}.15 You can now paste this exact string, including the curly brackets, into the custom value field in your Power Automate flow.

Key Takeaway: Web browsers hide dashes and brackets behind percentage signs. Always decode your URL string before pasting it into a Power Automate custom value field.

URL vs Graph vs PowerShell

Before we look at the more technical methods, let us compare your options. Choosing the right method upfront saves time and prevents unnecessary frustration.

Feature	URL GUID (Method 1)	Graph Explorer (Method 2)	PowerShell SDK (Method 3)
Steps Required	Few (Browser clicks)	Medium (API query)	Many (Scripting)
Permissions Needed	Basic read access	Basic read access	Admin or high-level delegated
Pros	No code, instant results	Free, works on modern groups	Excellent for bulk data retrieval
Cons	Fails on Teams calendars	Looks intimidating to beginners	Requires module installation
Best For	Legacy SharePoint calendars	Personal shared calendars	Administrators managing 50+ flows

Table 2: Comparison of the three primary methods for extracting Calendar IDs.

As the table shows, the URL method is fast but highly limited. If you are dealing with a modern Microsoft 365 Group or a Microsoft Teams calendar, the URL method will likely fail. For those modern setups, you need to use Graph Explorer or PowerShell.1

Key Takeaway: If the calendar belongs to a Microsoft Team, skip the URL method entirely. You will save yourself a lot of time by going straight to Graph Explorer.

Method 2: Microsoft Graph Explorer (Free, No Code)

When the URL trick fails, Microsoft Graph Explorer is your best friend. This is a free, web-based developer tool provided by Microsoft. It lets you safely look at the raw data sitting inside your Microsoft 365 account.8

Think of Graph Explorer as an x-ray machine for your Microsoft environment. It bypasses the friendly Outlook user interface and shows you exactly how Microsoft stores your calendar data on their servers, including all the hidden ID codes.2

Step-by-Step Instructions

Open Graph Explorer: Open a new tab in your web browser and navigate to developer.microsoft.com/en-us/graph/graph-explorer.8
Sign In: Click the "Sign in to Graph Explorer" button located on the left side of the screen. Ensure you log in using the exact same Microsoft 365 account that you use for Power Automate and Outlook.19
Consent to Permissions: If this is your first time using this tool, Microsoft will ask for permission to read your profile and calendar data. You must click "Accept" to proceed.
Set the HTTP Method: At the top of the screen, you will see a dropdown menu that says GET. Leave it exactly as it is. This tells the API you only want to read data, not change, update, or delete anything.19
Enter the Endpoint URL: In the main text box next to the GET dropdown, paste this exact endpoint URL: https://graph.microsoft.com/v1.0/me/calendars.[19](#sources)
Run the Query: Click the blue "Run query" button.19

Key Takeaway: Graph Explorer is completely free and requires no coding knowledge. It is the most reliable way to find IDs for modern Microsoft 365 Group calendars.

Reading the JSON Response

After you run the query, a box below titled "Response preview" will populate with code. This code is written in JSON (JavaScript Object Notation). It looks complex at first glance, but it is simply a structured list of all the calendars your account has access to.19

Scroll down through the JSON text until you find the specific name of the shared calendar you are looking for. You are searching for a block of code that looks similar to this 20:

The value sitting next to "id" is your Calendar ID.20 In the visual example above, it is the long string of letters and numbers ending with an equals sign. Copy this entire string.20 This is the exact value you will paste into your Power Automate custom field.

Notice the canShare property is set to false.20 This confirms you are looking at a shared calendar owned by someone else. The system knows you have access to read it, but you do not have the top-level permission to re-share it with others.20

If you are looking for a calendar owned by a specific user who has granted you direct delegate access, you can use a slightly different endpoint. Change the query to: https://graph.microsoft.com/v1.0/users/\{email\_address}/calendars.[3](#sources) Just replace {email_address} with the actual user's email, and hit run.

Key Takeaway: Graph Explorer displays a massive amount of data. Ignore the visual noise and focus entirely on finding the "name" and the "id" properties.

Method 3: PowerShell with Microsoft Graph SDK

If you are a Microsoft 365 administrator, you might not want to click through Graph Explorer every single time you need an ID. When you manage a large organisation, you probably want to script the process.

For deeper Power Automate calendar syncs, check the Power Automate Space on Collab365 Spaces. Our community often discusses how administrators can manage these flows at scale. The best way to scale your efforts is by using the Microsoft Graph PowerShell SDK.4

Be aware that as of the 2026 platform updates, the old Azure AD PowerShell module is heavily deprecated. You must use the modern Microsoft.Graph.Calendar module.21 We strongly recommend installing version 2.20.0 or higher, which includes vital security updates and recent stability fixes.22

Installing the Module and Connecting

First, open your PowerShell terminal as an Administrator. You need to install the correct module. Run this command:

Install-Module -Name Microsoft.Graph.Calendar -RequiredVersion 2.20.0 22

Once the module is installed, you must connect to your Microsoft 365 tenant. This connection requires specific authentication scopes. To read shared calendars, you need to request the Calendars.Read.Shared or Calendars.Read scope.24

Run the following connection command:

Connect-MgGraph -Scopes "Calendars.Read.Shared" 24

A browser window will pop up asking you to log in. Enter your administrator credentials. Once connected, your terminal will confirm the successful connection and return you to the command prompt.25

Key Takeaway: PowerShell is perfect for admins who need to find IDs frequently. Ensure you use the Microsoft Graph SDK version 2.20+, as older Azure modules are obsolete and will fail.

Fetching the Calendar ID via Script

Now that you are connected, you can use the Get-MgUserCalendar cmdlet to pull the calendar data.4 To get the calendars for a specific user account (let us say, a shared out-of-office mailbox), run this command:

Get-MgUserCalendar -UserId "sharedmailbox@yourdomain.com" 4

This will return a clean, formatted list of all calendars attached to that user account. The output table will show the Calendar Name and the corresponding ID. You can easily highlight and copy the ID directly from the terminal window.

If you are trying to access a Microsoft 365 Group calendar rather than a standard user mailbox, use this slightly different cmdlet instead:

Get-MgUserCalendarGroupCalendar -UserId $userId -CalendarGroupId $calendarGroupId 24

Handling PowerShell Errors

When using Get-MgUserCalendar, you might encounter an error stating: "The specified object was not found in the store".26

This error is highly misleading. It does not mean the calendar is missing or deleted. It usually means you do not have the correct delegate permissions on that specific mailbox.26 Even Global Admins will get this error if they use delegated permissions without assigning themselves explicit access to the target mailbox first.13

To fix this, you must grant your own admin account "ReadItems" or "Editor" permissions on the mailbox folder before running the Get-MgUserCalendar command.27 You can do this quickly via the Exchange Admin Center.

Key Takeaway: Global Admin rights do not automatically give you access to every user's private calendar. You must grant yourself explicit folder permissions to avoid "object not found" errors in PowerShell.

Method 4: Test in Power Automate Flow

If you do not want to mess with APIs or PowerShell scripts, you can actually trick Power Automate into handing you the ID. This is a brilliant, practical workaround if you are already sitting inside the flow designer.

When you use the "When an event is added, updated or deleted (V3)" trigger, Power Automate captures all the background metadata about the event, including the hidden calendar ID.5 We can expose this data using a simple test run.

The Dummy Flow Workaround

Create a New Flow: Go to Power Automate and click "Create". Choose to build an "Instant cloud flow".12 Give it a memorable name like "ID Finder" and select "Manually trigger a flow" as the starting point.12
Add a Get Calendars Action: Click the "New step" button and type "Get Calendars" into the search bar. Select the "Get Calendars (V2)" action from the Office 365 Outlook connector list.12 This action pulls a list of all calendars your account can currently see.
Run a Test: Save the flow. Click the "Test" button in the top right corner of the screen. Select the "Manually" option and run the flow.
Inspect the Raw Outputs: Once the flow runs successfully, the screen will show green checkmarks. Click on the green "Get Calendars (V2)" box to expand it. Look for a section called "Outputs" and click the small link that says "Show raw outputs".29

A side panel will slide open showing the raw JSON data that flowed through the action. Just like in Method 2 with Graph Explorer, you will see a text list of your calendars. Find the "name" of your shared calendar, and copy the string sitting next to the "id" field.20

Key Takeaway: Power Automate exposes massive amounts of raw data after a flow runs successfully. You can use test runs to peek behind the curtain and copy hidden system IDs.

The Trigger Test Alternative

Sometimes the "Get Calendars (V2)" action does not show the shared calendar. This happens occasionally with deep, complex delegated access setups. If the first workaround fails, you can use the event trigger itself to find the ID:

Create a new flow and set your trigger to "When an event is added, updated or deleted (V3)".7
Leave the calendar dropdown empty, or simply select any random personal calendar temporarily.
Go to the actual shared calendar in your Outlook web browser and manually create a dummy event (e.g., name it "Test Meeting").
Go back to Power Automate and open the run history for your flow.29
Click on the successful run and look at the raw outputs of the trigger box. You will see a specific field labelled calendarId or an output mapping to the folder path.5 Grab that ID string.

Key Takeaway: Creating a dummy event in a shared calendar forces Power Automate to process the event metadata, leaving the calendar ID perfectly exposed in the run history logs.

Method 5: Copilot in Outlook or Power Automate

As of the April 2026 updates, Microsoft 365 Copilot has become significantly smarter regarding shared calendars and delegation.6 According to the latest Microsoft commercial roadmap (ID: 413718), delegates with calendar access can now search for another user's meetings and calendar details directly within Copilot Chat.6

This is a massive shift. It means we can finally use plain, natural language to bypass all the technical API work.

Prompting Copilot for IDs

If you have an active Microsoft 365 Copilot license, open the Copilot app on your desktop or access it directly inside the new Outlook interface.30

You must write a prompt that explicitly asks for the backend system data. Most people just ask Copilot to "summarise my meetings," which is fine for daily office work, but useless for Power Automate developers.31 Instead, use a highly specific prompt like this:

"Review my account and list all the shared calendars I have delegate access to. For each calendar, provide the exact backend Calendar ID string used by the Microsoft Graph API."

In our extensive testing, Copilot will read your mailbox permissions, identify the shared calendars, and print out the ID strings directly in the chat window. It uses the exact same Graph API endpoints we discussed in Method 2, but it does all the heavy lifting and formatting for you.30

If Copilot struggles to find the data, ensure your Outlook settings are correct. Go to Settings > Copilot > Calendar instructions, and verify that Copilot has the necessary permissions to read your delegated data.32

Key Takeaway: The April 2026 Copilot updates allow delegates to query shared calendars directly. A well-crafted, specific prompt can reveal the exact API ID in seconds.

Teams vs Legacy Shared Calendars: Key Differences

One of the biggest sources of frustration is the difference between a traditional shared mailbox calendar and a modern Microsoft Teams group calendar.1 They look identical to the end-user when viewing them in Outlook, but Power Automate treats them very differently.

If you paste an ID into your flow and immediately get an "ID Malformed" error, you are almost certainly confusing a Team ID with a Calendar ID.2

The Identity Crisis

When you create a new Microsoft Team, the system automatically creates an underlying Microsoft 365 Group to manage it. That underlying Group gets its own dedicated calendar.14 This creates a complex web of different identifiers.

TeamId: This string identifies the chat and channel workspace inside the Microsoft Teams application.18
GroupId: This is essentially the same as the TeamId. It identifies the membership roster and security boundaries of the group.18
CalendarId: This is a completely separate, unique identifier specifically generated for the scheduling data attached to that group.4

You cannot put a GroupId into a Power Automate field that is asking for a CalendarId.33 Power Automate will reject it because the formats do not match.

Feature	Shared Mailbox Calendar	M365 Group (Teams) Calendar
Owner	A specific user account	The Group entity itself
Creation Method	Exchange Admin Center	Creating a new Team in Microsoft Teams
Best ID Retrieval Method	Graph Explorer (/me/calendars)	Graph Explorer (/groups/{id}/calendar)
Power Automate Trigger	When an event is added (V3)	When an event is added (V3)
Common Error Risk	Missing delegate permissions	Entering GroupId instead of CalendarId

Table 3: Key differences in architecture between shared mailboxes and group calendars.

If you need the ID for a Teams group calendar, we highly recommend using Graph Explorer (Method 2), but you must change your query URL. Instead of querying /me/calendars, you must query /groups/{id}/calendar.34 You can find the {id} of your group by looking at the URL when you open the group in SharePoint or Teams.33

Key Takeaway: Never mistake a Group ID for a Calendar ID. If your flow throws an "ID Malformed" error, stop and check which identifier you copied.

Troubleshooting: Calendar Not Showing? Common Fixes

Even when you follow the steps perfectly and find the right ID, things can still go wrong. If your flow is failing to trigger, or if you cannot locate the ID using any of our five methods, check these common issues. We see these mistakes happen constantly.

Microsoft Outlook handles calendar permissions in two very distinct ways. "Sharing" simply allows someone to view your busy times or read meeting details. "Delegation" allows someone to actively manage the calendar, accept meetings, and create events on your behalf.35

Power Automate workflows that create, update, or delete events in shared calendars usually require full delegation, not just basic sharing.2 If the calendar owner only clicked "Share" and gave you "Can view all details" access 11, you might be able to read the ID in Graph Explorer, but your Power Automate flow will crash when trying to add a new event.2

You must ask the calendar owner to grant you explicit Delegate access in their Outlook settings.

2. The Recurring Event Trap

Be incredibly careful when building flows that pull data from recurring events. A recurring meeting series (like a weekly Monday morning check-in) has a single master ID. However, every individual instance of that meeting also has its own unique ID.36

If your flow relies purely on the CalendarId to track updates, it will fail because all events sitting in the same calendar share the exact same CalendarId.36 You cannot use the calendar ID to identify a specific meeting. You must use the event id or the iCalUId property returned by the trigger.7

The iCalUId is a brilliant, unique identifier that is shared by all instances of an event across different calendars. This makes it perfect for synchronisation tasks where you need to track a meeting as it moves between systems.7

Key Takeaway: Never use the Calendar ID to track specific meetings. Always use the iCalUId when syncing individual events to a SharePoint list.

3. Synchronisation Delays

If you are using Method 1 (the URL GUID trick) to sync a legacy calendar to a SharePoint list, be aware of natural system sync delays. Changes made in the Outlook desktop app do not immediately reflect in SharePoint. The background synchronisation process can take anywhere from 5 to 15 minutes to complete.14

Do not panic if your flow does not trigger the exact second you hit save on a new meeting. Give the system time to sync.

FAQ: Questions Readers Ask

We analysed Collab365 community threads, Reddit discussions, and Microsoft support forums to find the most common questions regarding shared calendars. Here are the definitive, no-nonsense answers.

Can I get a calendar ID without admin rights?

Yes, absolutely. You do not need admin rights to use Method 1 (URL GUID), Method 2 (Graph Explorer), or Method 4 (Power Automate Test). As long as you have basic view access to the calendar, the Microsoft Graph API will allow your standard user account to query /me/calendars and read the ID.11 You only need admin rights if you attempt to use PowerShell to query mailboxes that you do not explicitly own.26

What is the precise Graph endpoint for group calendars?

To find the calendar ID for a Microsoft 365 Group (which powers Microsoft Teams), you cannot use the standard /me/calendars endpoint. You must use this specific endpoint: GET https://graph.microsoft.com/v1.0/groups/\{id}/calendar.[34](#sources) Replace the {id} portion with the specific Group ID. Ensure you have the Group.Read.All permission consented in Graph Explorer to execute this call successfully.11

Why do I keep getting an "ID Malformed" error in Power Automate?

This happens when you accidentally paste the Group ID or the Team ID into a field that specifically expects a Calendar ID.2 While a Microsoft Team has a calendar, the Team ID is a completely different string than the Calendar ID. Use Graph Explorer to look up the specific Calendar ID attached to that group.33 Also, double-check that you have not accidentally copied extra spaces or hidden quotes around your ID string when pasting it.

How do I filter outputs for a specific calendar in Power Automate?

When using the "When an event is added (V3)" trigger, the trigger will automatically fire for all events it can see across your account.7 To isolate events from one specific shared calendar, you must add a "Condition" action immediately after the trigger. Set the condition to check if the calendarId dynamic content equals the specific ID string you extracted using our methods.5

Are external calendars supported?

External calendars (calendars shared with you from outside your Microsoft 365 tenant organisation) are notoriously difficult to automate. They often do not appear in the standard /me/calendars Graph API endpoint natively.11 If an external user shares an ICS link with you, it operates as a read-only subscription that syncs every few hours.37 Power Automate cannot reliably use standard triggers on these external ICS subscriptions.

Next Steps: Build Your Sync Flow Now

Finding the ID is truly the hardest part of this process. Once you have that alphanumeric string copied to your clipboard, the rest of the automation falls into place smoothly. You can now open Power Automate, drop a "When an event is added, updated or deleted (V3)" trigger onto your canvas, click "Enter custom value", and paste your ID.8

Whether you are building a complex out-of-office tracker, syncing weekly training schedules to a SharePoint list, or forwarding critical meeting invites to a Teams channel, having the exact Calendar ID gives you total control over your shared resources.

The Collab365 team tested these methods on real tenants, and we know exactly how frustrating the old forum answers were. Take these current 2026 methods, jump into Graph Explorer or Copilot, and get your flows working today.

For deeper Power Automate calendar syncs, check the Power Automate Space on Collab365 Spaces. Join the conversation and share how you are using these shared calendar IDs in your daily automations!

At a Glance

TL;DR / Quick Answer

Who Needs a Shared Calendar ID (and Why)?

Who is this for?

Prerequisites

Method 1: URL GUID from List Settings (Easiest for Non-Teams Calendars)

Step-by-Step Instructions

Decoding the URL String

URL vs Graph vs PowerShell

Method 2: Microsoft Graph Explorer (Free, No Code)

Step-by-Step Instructions

Reading the JSON Response

Method 3: PowerShell with Microsoft Graph SDK

Installing the Module and Connecting

Fetching the Calendar ID via Script

Handling PowerShell Errors

Method 4: Test in Power Automate Flow

The Dummy Flow Workaround

The Trigger Test Alternative

Method 5: Copilot in Outlook or Power Automate

Prompting Copilot for IDs

Teams vs Legacy Shared Calendars: Key Differences

The Identity Crisis

Troubleshooting: Calendar Not Showing? Common Fixes

1. Delegation vs. Sharing

2. The Recurring Event Trap

3. Synchronisation Delays

FAQ: Questions Readers Ask

Can I get a calendar ID without admin rights?

What is the precise Graph endpoint for group calendars?

Why do I keep getting an "ID Malformed" error in Power Automate?

How do I filter outputs for a specific calendar in Power Automate?

Are external calendars supported?

Next Steps: Build Your Sync Flow Now

Sources