No it is not possible, each company will only report on its own data

the different reports would need to be exported to excel one at a time, and combined in excel to get a combined report

Resolution for 'combined report issue: 'Is it possible in QB-online – while having installed many companies – to have an overall reporting and snapshots??' available: Yes.

The combined report issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the combined report issue yourself by looking for a resolution described in the article. If it is a complex combined report issue or you are unable to solve the issue, you may contact us by clicking here or by using other combined report support options.

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