Data access after Project Online (PWA) retirement

Hi Pablito,

That's a great and very practical question, and unfortunately the answer is not what most people want to hear.

Based on the information I have gathered from multiple direct interactions with Microsoft (support cases, partner community meetings, and official replies on Microsoft Learn), the entire PWA site collection will become unavailable after September 30, 2026. This means that any content hosted on that site collection, whether it is related to Project Online or not, will no longer be accessible.

So to answer your question directly: yes, your custom lists created on the PWA site will also become unavailable, even though they are not related to PWA functionality and are used for other business processes.

The key point here is that Microsoft is decommissioning the PWA site collection as a whole. It does not matter whether the content on that site is project data, a custom list, a document library, or anything else. If it lives on the PWA site (or on a subsite created under the PWA site collection), it will be gone after retirement.

What you should do before September 30, 2026:

1. Identify all custom lists and non-PWA content stored on your PWA site collection.
2. Migrate those lists to a separate, standalone SharePoint site that is not tied to the PWA instance. You can use SharePoint native tools, Power Automate flows, or third-party migration tools to move the data.
3. Update any links, integrations, or automations that reference those lists to point to the new location.
4. Do not wait until the last moment. The retirement is a hard stop with no grace period and no read-only window guaranteed by Microsoft.

I've asked Microsoft this same question multiple times through different channels, and the answer has been consistent: everything under the PWA site collection goes away. Plan accordingly.

Hope this helps! If you have follow-up questions, feel free to reply here.