Archive or Delete Completed Planner Tasks with Power Automate

Microsoft Planner does not provide a general archive action in the Power Automate connector. Start with Planner's filters and views. If completed tasks genuinely need removing, copy the records you must retain to an archive first, verify the copy, then delete with a deliberately guarded flow.

Microsoft currently labels Delete a task as Preview. That makes an unattended mass-deletion flow a poor default.

Fact-checked against the current Microsoft Planner connector on 24 August 2026.

Decide whether deletion is necessary

Completed tasks are history. They can contain assignments, dates, checklist information and business evidence.

Before automating deletion, ask:

• Can a filtered Planner view solve the clutter?
• Is the plan still used for reporting or audit?
• What retention policy applies?
• Who is authorised to delete tasks?
• How would a mistaken deletion be recovered?

Do not claim that completed tasks are slowing Planner unless you have evidence from your tenant. Visual clutter and service performance are different problems.

Safer pattern: archive, verify, delete

Create a SharePoint list for the fields you need to retain, for example:

• Planner task ID
• Plan ID
• Title
• Assigned users
• Percent complete
• Start and due dates
• Archived at
• Source run ID
• Deletion approved
• Deleted at

Make the Planner task ID unique in the archive list so reruns do not create multiple archive records.

Build the flow in report-only mode first

1. Create a scheduled or manually triggered cloud flow.
2. Add Planner > List tasks and select the plan.
3. Filter the returned tasks where Percent complete equals 100.
4. Create or update the matching SharePoint archive record.
5. Send the proposed deletion list to the plan owner.
6. Stop the flow without deleting anything.

Run this for at least one real review cycle. Check task counts, blank fields, recurring operating patterns and tasks that were completed accidentally.

Add an age rule only from a reliable date

Do not invent a completed date from the due date. If the connector output does not give you a completion timestamp you can prove, record the first archived date and require a later cleanup run to wait for your retention period.

This produces a defensible rule: the task has been complete and archived since a known date controlled by your process.

Add deletion as a separate approved flow

Once the report-only output is trusted:

1. Query archive rows that are approved, old enough and not marked deleted.
2. Re-read the Planner task.
3. Confirm it is still complete.
4. Call Delete a task (Preview) using the stored task ID.
5. Mark the archive row deleted only after the action succeeds.
6. Record failures for human review.

Keep concurrency off initially. A slow, traceable cleanup is preferable to parallel irreversible calls.

Important limitations

• Delete is not archive. The Planner item is removed.
• The connector action is currently Preview and can change.
• The Planner connection belongs to a user and is not shareable in the same way as every other connector.
• Plan and group permissions still apply.
• Attachments and every detail you care about need their own tested archive mapping.

If the task data is governed or legally significant, do not use this pattern until the responsible owner approves the retention and recovery design.

Common mistakes

Deleting every task at 100 percent

Completion alone is not a retention policy. Add archive proof, age, explicit approval and a second read.

Assuming the archive is complete

Compare the archived record with the Planner task. Task details, assignments and checklist items may require additional connector actions.

Creating duplicates on every schedule

Use Planner task ID as the archive key and update the existing row.

Turning on concurrency too early

Parallel deletion makes throttling, partial failure and incident recovery harder. Prove the serial path first.

Microsoft sources

• Microsoft Planner connector reference
• Power Automate limits and configuration
• Avoid anti-patterns in Power Automate

Review the deletion boundary with another maker

Bring the report-only output and retention rule to the Power Automate Builders Space before switching on deletion.