Lease addendums allow landlords and tenants to change terms or add rules during a tenancy—if drafted and signed properly. Here’s a complete guide to common addendums, legal requirements, and downloadable templates.
Key takeaways
- All addendums must be in writing and signed by both parties to be enforceable.
- Addendums cannot override state/local law (habitability, discrimination, notice, etc).
- Be specific—avoid vague language (“may be allowed”) in favor of clear rules, dates, amounts, and signatures.
- Keep addendums with the original lease, and give copies to all parties.
Common Lease Addendums
- Pet addendum
- Roommate/subletting addendum
- Smoking/cannabis prohibition
- Rent increase/change in payment terms
- Appliance/furniture or parking changes
- Move-out or early termination agreement
Sample Lease Addendum (Oregon/California Compliant)
Lease Addendum
This Addendum is attached to and made part of the lease dated [Lease Date], for the property at [Address], between [Landlord Name] (“Landlord”) and [Tenant Name] (“Tenant”).
1. Purpose: [e.g., “To allow one pet under 25 lbs with a $200 deposit.”]
2. Effective Date: [Date]
3. Terms/Rules: [List specific rules or changes here]
4. All other lease terms remain unchanged.
Landlord: ________________________ Date: _______
Tenant: _________________________ Date: _______
This Addendum is attached to and made part of the lease dated [Lease Date], for the property at [Address], between [Landlord Name] (“Landlord”) and [Tenant Name] (“Tenant”).
1. Purpose: [e.g., “To allow one pet under 25 lbs with a $200 deposit.”]
2. Effective Date: [Date]
3. Terms/Rules: [List specific rules or changes here]
4. All other lease terms remain unchanged.
Landlord: ________________________ Date: _______
Tenant: _________________________ Date: _______
Pitfalls & Legal Traps
- Never use addendums to skirt rent cap, notice, or habitability laws—these can be voided and expose you to fines.
- Get written, dated signatures from all parties—verbal agreements don’t hold up in court.
- Always use specific language (“Tenant may keep 1 cat, max 15 lbs, with $250 additional deposit”)—not vague terms.
- Consult an attorney or local landlord association for major changes or anything not covered in state law.
Tip: Have all parties initial every page of the addendum for extra enforceability.
Caution: If an addendum violates tenant rights or state/local law, it may be thrown out in court.[1]