Cannot delete this invoice as a check has been applied to this invoice
Sage 50 blocks invoice deletion when a payment check is linked to it; you must remove the link first or void instead.
When Sage 50 tells you “Cannot delete this invoice as a check has been applied to this invoice,” it means a payment — typically a customer check or vendor bill payment — is currently linked to that invoice. Sage 50 will not let you delete the invoice because doing so would leave an orphaned payment pointing at nothing. The invoice and the check are joined, and the system protects that link.
Unlink the check first
The safest approach is to reverse the connection before touching the invoice. Open the check that is applied to the invoice and remove the application — zero out the amount applied in the payment allocation screen, then save the check. Once the check is no longer linked, return to the invoice and delete it. The check itself remains in your records, just unapplied.
If you are not sure which check is involved, look at the invoice’s payment history or activity tab. Sage 50 typically shows the payment date and reference there.
Void instead of deleting
If unlinking is not practical — for example, the check has already been reconciled in a closed period — voiding the invoice is usually the better choice. Voiding preserves the audit trail by negating the invoice’s effect rather than removing it entirely. The exact menu path depends on your version of Sage 50 and whether you are in the US (Peachtree) or Canadian (Simply Accounting) edition, so if the void option is greyed out or missing, that often points to a period-lock or a reconciliation dependency.
Check for reconciliation or period locks
A check that has been reconciled in bank reconciliation cannot be freely edited or unlinked without first undoing the reconciliation for that period. Similarly, if the invoice sits in a fiscal year that has been closed, Sage 50 will block changes to protect your historical balances. In both cases you need to reopen the period or undo the reconciliation before Sage 50 will cooperate — and that has accounting consequences you should weigh carefully.
When the file itself is the problem
Occasionally this message persists even after you have confirmed no check is applied, or the invoice appears in lists but cannot be opened, edited, or deleted at all. That pattern suggests the link between the invoice and the payment is damaged at the database level — the records are out of sync with what the screen is showing you. This is a data-integrity issue inside the company file, not a normal workflow block, and attempting force-deletion through database tools can corrupt the file further.
If you have ruled out the straightforward causes and the invoice still will not delete or void, the file likely needs professional attention. Our engineers routinely repair damaged Sage 50 and Simply Accounting databases where transaction links have broken — send us the file for a free evaluation and we will tell you exactly what is wrong and what it takes to fix it.