An ACH return is a payment that bounces after the fact. Because ACH is a batch system, a rent debit can show as processing or even complete and then come back days later when the tenant's bank rejects it. Every return carries a standardized code identifying the reason — the common ones for rent are insufficient funds, a closed or unable-to-locate account, and an authorization that was revoked or disputed. The reason matters: an insufficient-funds return is often worth retrying, while a revoked-authorization return means stop and talk to the tenant, since re-debiting a revoked authorization creates compliance problems.
Operationally, returns are why rent accounting needs a two-step mindset: record the payment when it is initiated, but do not treat the ledger as settled until the return window has passed, and reverse cleanly — including any late-fee implications — when a return lands. Many leases provide a returned-payment fee; whether and how much is governed by the lease and local law. A pattern of returns from one tenant is an early-warning signal worth a conversation, not just a retry loop.
This is general educational information, not legal or tax advice. Rules vary by state and locality and change over time — check your local law and confirm specifics with a qualified professional.