Renting
What Is a Lease Addendum?
By FixMyContractLast updated Sep 25, 20262 min read
A lease addendum is a separate document that adds to or changes an existing lease — for example, a pet agreement, a parking space or a rent concession. Once both sides sign it, it becomes part of the lease.
Common lease addenda
Pets, parking, storage, utilities, smoking, renewal terms, a rent concession, or rules the building added later.
What to check before signing one
Whether it changes anything in the main lease — rent, fees, the end date — and whether it says which document wins if the two disagree.
Addendum or amendment?
People use both words. An addendum usually adds something new; an amendment usually changes existing wording. The label matters less than what the text does.
Example: a pet addendum
A typical pet addendum names the animal, sets a pet deposit or monthly pet rent, says who pays for damage, and adds rules such as leash or noise rules. Read the fee lines against the main lease: if the lease already mentions a pet fee, the addendum should say whether it replaces that fee or adds to it.
Questions to ask before you sign one
- Does this change the rent, any fee, or the end date of my lease?
- If the addendum and the lease disagree, which one wins?
- Does it end when the lease ends, or carry over into a renewal?
- Will I get a signed copy of the lease and the addendum together?
If one arrives in the middle of your lease
An addendum changes your agreement, so read it with the same care as the original lease. It is reasonable to ask which clause of your current lease it relies on and why it is being added now.
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This is information, not legal advice.