How Much Does an ADU Permit Cost in Los Angeles?

If you’re planning an accessory dwelling unit (ADU) in Los Angeles, your first question probably isn’t “what color should the cabinets be?” It’s how much does an ADU permit cost in Los Angeles? Permits don’t just nibble at your budget — they shape your whole project timeline. Whether you’re eyeing a garage conversion or a full backyard unit, understanding permit fees, timelines, and city quirks will save you from costly surprises.

Why Permit Costs Matter Now

Los Angeles homeowners are sprinting to start ADUs before year-end. Demand for rentals is strong, California laws are encouraging growth, and permits are the ticket that gets you out of the driveway. Permits affect your budget, timeline, and even your design. Think of them as referees: no play starts until they blow the whistle.

Understanding ADU Permit Fees

Permit costs in Los Angeles depend on size, type, and valuation. A garage conversion permit in Los Angeles typically lands on the lower end, while detached ADUs require more reviews and fees【planning.lacity.gov】. Other fees often apply:

• Plan check fees for design review

• School impact fees (waived for ADUs under 750 square feet)

• Sewer and utility connection fees, which vary by property

  
  

Instead of guessing, LADBS provides an online permit fee calculator where you can input project details and see your estimated fees before applying. 💡 Pro tip: Don’t skip the calculator. It’s like peeking at the bill before the waiter sets it down — you’d rather know before dessert.

Permit Timelines vs. Reality

State law says ADU permits should be approved in 60 days. In practice? LADBS backlogs and plan-check corrections often stretch that timeline【aduwestcoast.com】. It’s like telling a friend “I’ll be there in five” while sitting on the 405. The law might say one thing, but the gridlock says otherwise.

The Full Permit Path: From Plans to Keys

Here’s how a permit application usually travels through the system:

1. Design & Plans – Architectural, structural, electrical, plumbing, and energy (Title 24) drawings.

2. Preliminary Review (sometimes) – Planning or zoning checks setbacks, easements, slopes.

3. Formal Plan Check – Multiple reviewers comb through your plans, issue corrections, and wait for resubmittals.

4. Permit Issuance – Once reviewers sign off, you pay fees and pull permits.

5. Inspections – Foundation, framing, plumbing, electrical, final. Each stage gets a green light.

6. Utility Coordination – Sewer, water, or electric departments may require upgrades or deposits.

7. Certificate of Occupancy – The final stamp that makes your ADU legal to rent or live in.

   
   

What Drives Permit Cost (and What You Can Control)

Not all fees are created equal. Here’s what makes costs climb — and what you can do about it:

• Project valuation – Fees scale with declared construction value. Keep it accurate, not padded.

• Square footage – Bigger unit, bigger systems, bigger review fees. Compact layouts can help.

• Impact fees – Waived under 750 sq ft, triggered above.

• Utility upgrades – New panels or sewer lines add both cost and time.

• Design complexity – Slopes, retaining walls, or tricky lots invite extra scrutiny.

• Corrections & resubmissions – Each round of corrections means more review hours.

• Multiple agencies – LADBS, Planning, Fire, Public Works — each may charge or delay.

  
  

🛠️ Myth versus reality: Homeowners often assume permit fees are flat across LA. In truth, every city plays by its own fee schedule — and they rarely compare notes.

LADBS Tools to Save Time (and Money)

The city actually gives you a few shortcuts if you know where to look:

• Permit Fee Calculator – Estimate fees before applying.

• ePlanLA / PermitLA – Submit plans and track status online.

• Standard Plans – Pre-approved ADU designs for faster review.

• Express Permits – Available for smaller, simpler projects.

  
  

Common Pitfalls That Add Cost

Avoid these rookie mistakes:

• Submitting incomplete or inconsistent plans.

• Forgetting early utility coordination.

• Ignoring zoning setbacks or height rules.

• Redesigning mid-review and triggering new corrections.

• Waiting until late to address grading, drainage, or soil issues.

  
  

🔍 Inspector note: Clean plans, consistent details, and labeled drawings keep reviewers moving faster — and lower everyone’s blood pressure.

Timeline Reality: The Real Clock

State law promises 60 days. Actual projects?

• Smooth reviews: 2–4 months

• Typical: 3–6 months

• Complex sites: longer, especially in coastal or hillside zones

  
  

Bottom line: build a buffer. Permits are not the place to gamble with deadlines.

Extra Fees That Surprise Homeowners

Beyond base permit costs, watch for:

• New address fees

• Construction or demo bonds

• Certificate of Occupancy fees

• Extra inspection trip charges

• Overtime inspection fees

• Utility/meter upgrade deposits

• Impact/development fees (school, traffic, parks, etc.)

  
  

City-by-City Differences

Permit processes shift once you cross city lines:

• City of Los Angeles (LADBS): Largest application volume, online lookup tool.

• Santa Monica: Extra design review, stricter plan checks.

• Burbank: Utilities run the show here.

• Beverly Hills & Pasadena: Separate fee schedules and design rules.

  
  

Crossing from one city to another in LA County is like switching from chess to checkers mid-game. Same board, totally different rules.

What to Ask Before Applying

Before you file your plans, get answers to:

• What are the base permit fees?

• Will school impact fees apply to my ADU size?

• Are sewer or electrical upgrades required?

• How long is the current plan check backlog?

• What design corrections are most common in my city?

  
  

Call to Action

Want the clearest picture? Try the LADBS permit fee calculator — then let us run a free ADU permit-fee audit to flag hidden costs. Still exploring? Browse our ADU design and planning services or garage conversion ADU services. The right prep now keeps surprises out of your future budget.

Checklist for Homeowners

• Confirm ADU size and type (garage conversion vs new).

• Check if you qualify for the under-750 sf school fee waiver.

• Use LADBS permit lookup to see past project history.

• Budget for sewer and utility connection fees.

• Ask about current plan check timelines in your city.

• Review correction notes before submitting plans.

  
  

Conclusion: Your Path to a Successful ADU

Navigating the ADU permit process in Los Angeles can feel overwhelming. But with the right information and tools, you can streamline your journey. Understanding the costs, timelines, and potential pitfalls will help you avoid surprises down the road. Remember, the earlier you start, the smoother your project will be. Let’s get those plans rolling!