Reference numbers are available for most all QuickBooks transactions - except for Deposits. (A memo field exists for Deposits, but not a Reference Number). Furthermore, users of QuickBooks may not even enter a reference number - the most common of which are Vendor Bills.
QuickBooks makes available another type of Reference Number called Transaction Number which is unique AMONG ALL TRANSACTIONS. It is not listed by default in QuickBooks reports, but can be added to any report:
An additional problem for pivot tables arises when grouping by reference number. If several transactions have no reference number, they would be grouped together as one lump sum. Use the Transaction Number instead.
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