
Hi @Jeff Penhale,
Currently, SharePoint Online does not provide a direct feature to restrict the upload of a single file based on its size because it's a shared setting for all the tenants.The default upload size for a single file in SharePoint Online is 250GB. This is designed by SharePoint.
Reference: File upload and download sizesWe apologize for any inconvenience this may cause and thank you for your understanding.
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