try this

in reports, enter purchases in the search box, select purchases by vendor detail, click customize

click row/column>more columns and check mark the field customer

run the report

the customer column will show the customer name selected and be blank if no customer was assigned to the bill/item

Resolution for 'billitem issue: 'Can I run a report for all expenses and bills that are not assigned to a customer?' available: Yes.

The billitem 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 billitem issue yourself by looking for a resolution described in the article. If it is a complex billitem issue or you are unable to solve the issue, you may contact us by clicking here or by using other billitem support options.

For more information about resolving issues related to billitem in Quickbooks/QBO or to get support for the issue 'Can I run a report for all expenses and bills that are not assigned to a customer?', click the link below: