The Security Deposit Funds Mismatch diagnostic in AppFolio compares two numbers: the GL balance for your security deposit account and the total shown in the Security Deposit Funds Detail report. In a clean set of books these two numbers are identical. When they're not, something in your security deposit accounting is wrong.

This diagnostic fires more often than most, and for a small number of specific reasons.

The most common cause is a non-resident transaction posted to the security deposit GL. This happens when a journal entry, a bill, or some other transaction is coded to the security deposit account instead of the correct GL. The Security Deposit Funds Detail report only tracks resident-related security deposit activity. If a non-resident transaction hits that GL, it shows up in the GL balance but not in the report total, creating a gap.

To find it, run the General Ledger report filtered to your security deposit GL account. Look for any transaction that isn't tied to a resident or a move-in or move-out workflow. Those are your problem entries. Reverse the transaction and recode it to the correct account.

The second common cause is past tenants who still have a balance in the system. If a tenant moved out but the security deposit wasn't fully processed through AppFolio's move-out workflow, their balance may still be sitting in the Funds Detail report. Find former tenants with open security deposit balances under the tenant ledger and complete the refund, withhold, or transfer workflow to close them out.

The third cause is a pending move-out. If a move-out is initiated but not completed, the deposit can be in a transitional state that creates a temporary mismatch. Complete the move-out workflow and the diagnostic usually clears.

Run this diagnostic every month before reconciling. A security deposit mismatch that goes unresolved for several months compounds quickly and can take significant time to unwind. It's much easier to fix when it's one transaction than when it's six months of accumulated entries.