PBIR 300 MB limit - what happens when downloading a copy of a larger existing report?

[P0WER_BI]

I've read in the documentation that the new PBIR format has a 300 MB max size limit for all report files. However, I haven't been able to find any information about what happens in this scenario:

If I have an existing report already published to the Power BI Service that exceeds 300 MB, and I attempt to download a copy of the PBIX file, what behavior should I expect?

Specifically:

• Will the download fail with an error message?
• Will it download but strip content to meet the limit?
• Will it download in PBIR-Legacy format instead?
• Or does the limit only apply to uploads/publishing?

With PBIR becoming the default format in January 2026 and eventually mandatory at GA, this seems like an important edge case for organizations with larger reports.

Has anyone tested this or encountered this situation? Any insight would be appreciated.

Thanks!

[cengizhanarslan]

The documented limit is about:

• the PBIR report definition size

• when saving / publishing from Desktop

• or when creating new reports going forward

It’s not a retroactive enforcement on content already stored in the Service. So I do not thşnk you would easily be able to hit hat 300MB limit since it does not store data. PBIR is the report definiton only containing pages, visuals, measures, etc.

[P0WER_BI]

Thanks - that clarification actually helps a lot. So just to make sure I understand correctly:

The 300 MB PBIR limit applies only to the report definition (pages, visuals, formatting, etc.), and is completely separate from the data/semantic model size?

So if I have a 1 GB PBIX file using Import mode, most of that size is the compressed data - not the report definition. The PBIR limit wouldn't affect my ability to download or work with these files at all, since the report definition portion is likely only a few MB?

If that's the case, that answers my question - I was conflating the overall PBIX file size with the report definition size. Appreciate the help!

[v-hashadapu · Accepted solution]

Hi @P0WER_BI , Thank you for reaching out to the Microsoft Community Forum.

Yes, you’ve got it right. The 300 MB limit is only for the PBIR report definition, not the data model. A large PBIX is large because of the imported data, which lives in the semantic model in the Service and isn’t part of PBIR. So existing large reports won’t be affected when you download or work with them, you were just mixing up PBIX size with PBIR size.

Thank you @cengizhanarslan  for your valuable response.

[P0WER_BI]

Thanks!