Co-signer / guarantor notice of default
By Justin Winter · Updated August 22, 2026
You can send a guarantor notice of default online in about two minutes: we typeset your letter and mail it USPS Certified with electronic Return Receipt for $14.99 all-in — proof of delivery that is typically required before pursuing a guarantor for payment.
A signed guarantee only helps you collect if you can show you actually notified the guarantor of the default — and did so the way the guarantee agreement (or your state) requires. Telling the tenant is not the same as telling the co-signer, and a phone call or email to the guarantor is easy to deny ever happened. Certified Mail with a delivery record closes that gap.
The guarantee is a separate contract
A lease guarantee is an agreement between you and the guarantor, not between the guarantor and the tenant. Many guarantee forms include their own notice clause — some require written notice within a set number of days of the default, others require notice before you can pursue the guarantor for a specific month's rent rather than the whole remaining lease term. Read the guarantee agreement itself before you send anything; it usually controls more than general landlord-tenant law does here.
What to include
Reference the guarantee by date and the rental address it covers, describe the tenant's default in specific terms (amount owed and the period it covers, or the lease clause violated), and state plainly what you are asking the guarantor to do — pay a specific amount, cure a specific violation, or simply be aware that liability under the guarantee has been triggered. Vague language here just invites a dispute later over what the guarantor was actually told.
How it works
- Open the template, fill in the tenant's default and the guarantor's contact information.
- Pay $14.99 (Certified + Return Receipt) — the letter prints and mails the next business day.
- You get a tracking number immediately and the signed delivery record once it arrives — your proof the guarantor was notified.
This template is a tool, not legal advice. Guarantor liability, required notice, and how much a co-signer can be held responsible for all vary by state and by the specific wording of the guarantee agreement — confirm both before sending, or consult an attorney if the amount at stake is significant.
Related guides
Common questions
Why does the guarantor need separate notice from the tenant?
A guarantee agreement is a separate contract from the lease, and many guarantee terms — or state law — require the landlord to notify the guarantor directly, with proof, before holding them responsible for the tenant's default.
What should this letter include?
The original guarantee date, a clear description of the tenant's default, and what you are asking the guarantor to do or pay, referencing the specific terms of the guarantee agreement.
Is this legal advice?
No — it is a template. Guarantor liability and required notice procedures vary by state and by the guarantee agreement's own terms.