You’ve agreed to a pet. Before anyone signs the addendum, make sure the paperwork says the same thing as the conversation, and that the charges fit Colorado law.

A text saying “the cat is fine” settles one question but can leave several others open. Is there an additional deposit? When does any pet rent begin? Which parts of the existing lease still apply? An addendum should answer those questions without introducing terms neither side discussed.

This is a Colorado-focused review guide, not a ready-to-sign legal form. Use current official rules and qualified local review for the property, tenancy and request. Keep any disability-accommodation request separate from the ordinary pet approval process.

Check Colorado's pet-charge limits

Colorado HB23-1068 limits an additional pet security deposit to $300 and requires it to be refundable. The act limits additional monthly pet rent to the greater of $35 or 1.5% of monthly rent. Confirm current statutory text and applicable requirements before using those limits in an agreement.

For a hypothetical $2,400 monthly rent, 1.5% is $36. That arithmetic illustrates the formula; it does not require charging $36 or establish that a charge applies to an assistance animal. Do not assume a charge may be multiplied by the number of animals without checking the governing rule.

Write out each agreed charge, when it starts and how often it is due. Then check the billing setup against the document. Calling everything a “pet fee” makes it harder for the resident to tell which money is refundable and which payment repeats each month.

Make sure the addendum fits this lease

Identify the parties, rental address, original lease and animal being approved. Include enough identifying information to avoid confusion without demanding unrelated records. Describe ordinary responsibilities such as waste cleanup, supervision, shared-area use and coordinating safe access for repairs.

Read the lease and addendum together. If one prohibits pets and the other approves this animal, the documents need to make the intended exception clear. Check the other attachments too. Once the terms agree, confirm the effective date, obtain the required signatures and give everyone a completed copy.

Use the accommodation process when it applies

Colorado HB26-1045 addresses assistance animals and reasonable accommodations, including circumstances in which supporting documentation may be requested. The request calls for an individualized review; it should not be decided by an ordinary pet restriction or a generic application score.

Ask only for information permitted and needed for the review. Restrict sensitive records and obtain qualified advice on the request, documentation and charges. Do not make signing an ordinary pet addendum a substitute for resolving an accommodation request.

Take a few useful photos now

If a pet is joining an existing tenancy, photograph and describe the relevant condition before the animal arrives. Include the date and let the resident point out anything you missed. An old scratch beside the back door should stay documented as an old scratch.

At move-out, compare the condition records and the facts behind each proposed deduction. Colorado's security-deposit protections in HB25-1249 are a separate review from whether a pet was authorized. Keep invoices, repair scope and communications with the condition evidence.

One last check before signatures

  • Correct rental, parties, lease reference and animal.
  • Clear responsibilities and no contradictory attachments.
  • Reviewed charges, timing and refundable-deposit treatment.
  • Any accommodation request addressed through its appropriate process.
  • Required signatures, delivered copies and matching records.

Start with the pet-review guide, then use the Colorado move-in checklist to document the home's condition.