Personal Guarantee Disputes: When Someone Co-Signed and Didn't Pay
When someone co-signs a loan, lease, or agreement and then the primary borrower defaults, the person left covering the debt often has a legitimate claim against the co-signer — or, from the other side, co-signers sometimes face claims they believe are unfair. Here's how this works.
Understanding the co-signer's obligation
A co-signer or personal guarantor typically agrees to be equally responsible for the debt if the primary party doesn't pay — this isn't a backup obligation that only kicks in after extensive collection attempts against the primary borrower; in most agreements, the guarantor can be held responsible directly and immediately once a default occurs.
Common scenarios
- A co-signed apartment lease — one tenant leaves owing rent, and the other tenant (who covered it) seeks reimbursement from the co-signer or the departing tenant directly
- A personal guarantee on a small business loan or lease — a business defaults, and the guarantor is pursued for the remaining balance
- A co-signed personal loan or car loan — the primary borrower stops paying, and the lender or the co-signer who covered payments seeks reimbursement
If you're the one who covered the debt and are pursuing the co-signer
Focus your evidence on:
- The signed agreement establishing the co-signer's obligation
- Payment records showing what you covered on their behalf
- Any communication acknowledging their responsibility or discussing repayment
If you're a co-signer being pursued and believe it's unfair
Common defenses worth checking:
- Whether you were properly notified of the default in a way the original agreement required
- Whether the amount being claimed matches what you actually agreed to guarantee — some guarantees are limited to a specific amount or time period, not open-ended
- Whether the primary party's payment history matches what's being claimed as unpaid — request documentation
This can also involve suing the primary borrower
If you covered a co-signed debt because the primary borrower defaulted, you may have a claim against both the primary borrower (who created the default) and, depending on your state and the specific situation, potentially the co-signer if their portion also wasn't covered — clarify who actually owes what portion before deciding who to name in your claim.
Calculating your claim
- The specific amount you paid covering the debt on the other party's behalf
- Any documented fees or penalties directly resulting from the default that you also had to cover
A note on business guarantees
Personal guarantees on business debts can sometimes involve larger amounts that exceed small claims limits — check your state's limit and consider whether waiving excess to remain in small claims makes sense for your situation.
This article is for general informational purposes and isn't legal advice. Co-signer and guarantor liability terms vary by the specific agreement and state law — review your agreement carefully before filing.