Mold is usually a habitability issue, not a separate law
Your state may well have no law that mentions the word "mold" by name. Instead, mold gets handled the same way any other serious defect does: through the general duty every landlord has to keep a rental unit safe and livable. If mold is significant — spreading across a wall, tied to a leak the landlord hasn't fixed, or causing symptoms for you or your family — that generally qualifies as a habitability problem the landlord has to address, the same as a broken furnace or a sewage backup would. See what is the warranty of habitability for how that underlying duty works.
What causes mold, and why the water problem matters more than the mold itself
Mold needs moisture to grow, so it's almost always a symptom of an underlying issue: a roof leak, a plumbing leak, poor ventilation, or condensation from an ill-fitted window. The EPA's guidance on mold and moisture is direct about this: if you clean up visible mold but don't fix the water problem causing it, the mold is very likely to come back. That's important context for a repair request — asking your landlord to "clean the mold" without also asking them to fix the leak behind it is unlikely to solve anything for long.
A concrete example of a state requiring a specific timeline
Where a state sets no mold-specific deadline, its general "reasonable time" repair rule is what applies — but a few states set a specific one. Washington, D.C.'s mold law, for example, requires a landlord who gets written or electronic notice of mold to inspect within 7 days and complete the repair within 30 days of that inspection. Where your state or city has a specific mold rule like this, it gives you a much firmer deadline to point to than a general "reasonable time" standard — check your local housing code or a tenant rights organization to see if yours does.
Health effects worth knowing about
According to the EPA, mold exposure can trigger allergic reactions — sneezing, a runny nose, red eyes, skin irritation — and can worsen asthma in people who are allergic to mold; it can also generally irritate the eyes, skin, nose, throat, and lungs whether or not you're allergic to it. If you or someone in your household is experiencing symptoms that line up with mold exposure, see a doctor and mention the mold — a medical record that ties your symptoms to the exposure date can matter if the dispute with your landlord escalates.
Your remedies if your landlord won't act
Once you've given written notice and a reasonable time has passed with no real fix, your options generally track the same menu available for any other unresolved habitability issue in your state: reporting the property to your local housing or health inspector, using repair-and-deduct or rent withholding where your state allows it (see can I withhold rent if my landlord won't make repairs and can I hire someone to make repairs and deduct it from rent), or ending the lease if conditions are genuinely uninhabitable. Which of these is actually available to you depends entirely on your state, so don't assume a remedy applies to you without checking.
Documenting the problem
Take dated, well-lit photos and video of every area with visible mold, and note any musty smell even where you can't see growth — hidden mold behind drywall or under flooring is common. Keep a written log of when you first noticed it and every time you notified your landlord. If the mold is extensive or you're not sure of the cause, a professional mold inspection can be strong independent evidence, though EPA guidance notes that sampling generally isn't necessary when mold is already visible — the priority is fixing the moisture source, not testing the mold itself. Honestkey can review your lease and flag whether it improperly shifts responsibility for conditions like this onto you.