How to Build a Power Automate Approval Flow from a Shared Mailbox

Create approval workflow turning inbox requests into tracked decisions.

Power Automate mastery here means move from scattered admin to controlled, measurable workflows.. This guide is written for operations leaders, analysts using microsoft 365.

Who this is for

Operations leaders, analysts using Microsoft 365.

The business problem

Shared inbox approvals have no ownership or tracking.

Before you start

• Microsoft 365 with shared mailbox.

How to build it

1Set up your SharePoint audit list

Create a SharePoint list called "Approval Log" with these columns:

Column	Type
RequestSubject	Single line of text
RequesterEmail	Single line of text
Amount	Currency
Decision	Choice (Approved/Rejected)
ApproverEmail	Single line of text
DecisionDate	Date/Time
Comments	Multiple lines of text

2Create the Power Automate flow

1. Go to make.powerautomate.com
2. Create a new Automated cloud flow
3. Trigger: When a new email arrives (V2)
4. Set the mailbox address to your shared inbox
5. Add a condition: Subject contains "approval" (or your trigger keyword)

3Parse the email for request details

If your emails follow a template, use Parse JSON to extract fields:

{
  "type": "object",
  "properties": {
    "amount": { "type": "number" },
    "requester": { "type": "string" },
    "description": { "type": "string" }
  }
}

If no template, use expressions like:

float(replace(json(decodeBase64(triggerOutputs()?['body']['bodyPreview'])))?['amount'], '£', ''))

4Add the approval action

1. Add Start and wait for an approval action
2. Approval type: Approve/Reject - First to respond
3. Title: Approval Request: @{triggerOutputs()?['body']['subject']}
4. Assign to: your approver email (or use a dynamic value)
5. Details: include the requester, amount, and description

5Log the decision

Add a Create item action (SharePoint):

• RequestSubject: triggerOutputs()?['body']['subject']
• RequesterEmail: from your parsed JSON or email From
• Amount: from your parsed JSON
• Decision: if(equals(outputs('Start_and_wait_for_an_approval')?['body']['outcome'], 'Approve'), 'Approved', 'Rejected')
• ApproverEmail: outputs('Start_and_wait_for_an_approval')?['body']['responder']['email']
• DecisionDate: utcNow()
• Comments: outputs('Start_and_wait_for_an_approval')?['body']['comments']

6Send confirmation back to requester

Add a Send an email (V2) action:

• To: requester email
• Subject: Your request has been @{outputs('Start_and_wait_for_an_approval')?['body']['outcome']}
• Body: Include decision, approver comments, and any next steps.

Common mistakes

What good looks like

Approval flow with trail.

Next steps

Once the first version is trusted, fold it into the weekly or daily operating routine that owns the outcome. A guide without a standing cadence becomes a forgotten document.

Relevant Digital Adaption links

• Fractional Business Analyst
• Services
• Power Automate Guides

Planned next guides in this track

• How to Build a Supplier Chase Workflow in Power Automate
• How to Automate a Daily Operations Pack with Power Automate

Frequently Asked Questions

Who should own this Power Automate guide?

The best owner is the person who understands both the business pain and the operational decision that must improve after the guide is used.

How should this guide be validated?

Run the proposed steps against a handful of live examples, then confirm the output with the team that already trusts the current process or source system.

What makes this worth publishing later?

It should answer a real operational problem with a repeatable workflow, clear ownership, and an outcome the reader can measure.