An honest comparison
Custom automation
vs Power Automate
Power Automate has an advantage none of the others have: if you already pay for Microsoft 365, a large part of it is effectively already bought. That makes it the correct first answer far more often than the automation industry likes to admit. It also makes the ceiling harder to see, because the cost of hitting it does not show up as a bill you notice.
Where it is genuinely the right call
Anything that stays inside the Microsoft world. An approval routed through Teams. A file that lands in SharePoint and needs to trigger a notification. A form response that becomes a list item. In that territory Power Automate is well integrated, governed by the tenant your IT already manages, and does not require a new vendor relationship. If your problem lives entirely in that world, use it, and be suspicious of anyone who tells you otherwise.
The two costs that arrive later
The first is premium connectors. The moment a flow needs to talk to something outside Microsoft, licensing changes shape, and what felt included becomes a per-user or per-flow line item that grows with adoption. The second is harder to see: flows accumulate in personal accounts. A business process ends up owned by an individual mailbox, invisible to everyone else, and when that person changes role the process becomes a mystery nobody wants to touch.
What ownership means differently here
Your data stays in your tenant, which is a real advantage and a genuine answer to the data-residency question. What you do not own is the logic: it lives in a designer, cannot be reviewed in a pull request, cannot be covered by a test suite, and cannot be moved anywhere else. For a notification that is irrelevant. For the process that produces your invoices it is the difference between an asset and a dependency.
The comparison, straight
| Power Automate | Custom system | |
|---|---|---|
| Best for | Processes inside the Microsoft 365 world | Operations your business depends on |
| Cost model | Partly included, premium connectors extra per user or flow | Built once, then nothing to rent |
| Governance | Your tenant, your IT policies | Your repository, reviews and history |
| Data residency | Strong: stays in your tenant | Strong: your database, your region |
| Testing | Run it and watch | Automated suites, staged rollout |
| Ownership of logic | In the designer, not portable | Versioned code you can move anywhere |
| Outside connections | Premium connectors, licensing changes | Any API, no licence per connection |
| Who can maintain it | Whoever knows the designer and has the licence | Any competent developer |
The signal that is specific to this tool
Not cost and not complexity, but ownership drift. Flows are created by individuals, in individual accounts, because that is the fastest way to get one working. A year later, several business-critical processes belong to personal accounts, nobody has an inventory, and a departure or a role change turns a working process into an outage nobody can explain. Ask one question to find out where you stand: can somebody produce a list of every flow currently running and who owns it. If the answer takes more than a day, that is the ceiling.
The rule of thumb
Stay with Power Automate while the process lives inside Microsoft, while a failure is inconvenient rather than expensive, and while the flows are inventoried and owned by the company rather than by people. Build when premium connectors have quietly become a growing line item, when the logic needs review and tests, when outside systems are central rather than incidental, or when a process is important enough that it must not live in a designer only one person understands.
Common questions, answered straight
Our IT prefers Microsoft for everything.
That is a legitimate position and often the right one for governance. It does not have to be all or nothing: the common shape is that Microsoft-internal processes stay where they are and the handful that reach outside get built properly. Nothing about custom code requires removing Power Automate.
Can we keep our flows and add to them?
Usually yes. A frequent first project is to move only the logic that has grown load-bearing into a tested service and leave the flow as the trigger. That is contained, reversible and does not disturb your tenant.
What about licence cost as we grow?
That is exactly the number worth checking before renewal. If premium connector licensing is scaling with headcount, a one-time build from $6,900 fixed scope often costs less over three years, and it stops scaling entirely once it exists.
What if Power Automate is the right answer for us?
Then the teardown will say so. I do not sell Power Automate work, so that recommendation costs me nothing and is worth something to you.
Related reading
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