What's the difference between perpetual accrual and period end accrual accounting?

For perpetual, or on-receipt accrual accounting, the receiving transaction automatically creates a receipt accrual journal entry that debits the receipt inventory and credits uninvoiced receipts.

After the received material is delivered to its final destination, the receipt inventory account is cleared and the material account is debited.

For period end accrual, no accounting is created at either material receipt or at delivery to the final destination.

Note: Period end accrual applies only to expense items because inventory items are always accrued on receipt.

For perpetual accrual accounting, you don't have to run the Create Uninvoiced Receipts Accruals process.

For period end accrual accounting, if the invoice for the receipt isn't created by period end, run the Create Uninvoiced Receipt Accruals process. The process generates the accrual and creates a reversing journal with an incomplete status. You must run the Create Accrual Reversal Accounting process to change the journal status to Complete and transfer the journal to the general ledger.

For perpetual accrual accounting, the invoice accounting debits the accrual account and credits the liability account.

For period end accrual accounting, the invoice accounting debits the expense account and credits the liability account.