Periodically, a vendor's invoice does not agree with the purchase order and / or the receiving slips for that order. Typically, this happens when freight was not quoted on the original purchase order and the vendor bills the company for freight on the vendor invoice (some other posibilities include pricing differences and incorrect shipment quantities).
The vendor's billing can be checked by running the report, Under/Over Voucher Slips, from the Receiving menu. This report lists receiving slips that have been incorrectly vouchered. If the amount vouchered does not equal the amount of the receiving slip, the receiving slip is printed along with its associated vouchers.
Receiving Slip Amount Received Voucher Voucher Amount
rs0101-02 214.40 vo0101-02 181.43
rs0112-02 2,3134.70 vo0120-01 2,2934.70
rs0294-02 52.13 No vouchers found
rs0309-01 4,375.29 vo0594-01 4,375.29
vo0594-02 4,375.29
As this report indicates, receiving slip rs0101-02 has been under vouchered by $32.97 ($214.40 - 181.43). Receiving slip rs0112-02 has been under vouchered by $20.00 ($2,3134.70 - 2,2934.70). Receiving slip rs0294-02 has not been vouchered at all. Instead, adjustments of some kind have been made (General Journal or Inventory Adjustment entries). Notice the last pair of lines for receiving slip rs0309-01. Apparently, either the vendor sent two copies of their invoice, or two vouchers were entered for the same vendor invoice. When more than one voucher references the same receiving slip, each voucher is listed with its voucher amount.
To find the cause of the under vouchering, you would need to check several documents. First, a report showing the detail of the receiving slips, Receiving menu: Receiving Slips by Vendor w/Detail, involved should be printed. Second, a report of the related vouchers, Accounts Payable menu: Vouchers by Vendor with Detail, should be printed. Lastly, the original source documents (vendor's packing slip and vendor's invoice) should be examined to determine the cause of the difference.
Incorrect vouchers can be changed using the Payable Vouchers data entry form on the Receiving menu. Freight adjustments can be made using the same data entry form, or using the Inventory Adjustment data entry form on the Inventory menu (see Chapter 35, Accounting For Freight for a discussion on freight).