What is a CSLB license?

A CSLB license is a contractor's license issued by the California Contractors State License Board, required for any construction project in California valued at $500 or more (labor and materials combined). The CSLB licenses three classifications: Class A (general engineering), Class B (general building), and Class C (specialty trades like roofing, electrical, plumbing). Licensees must pass trade and law exams, post a $25,000 surety bond, and maintain workers' compensation insurance for any employees.

How do I verify a contractor's license in California?

Use the CSLB "Check a License" tool at cslb.ca.gov — enter the contractor's license number or business name to see active status, classification, bond, workers' comp, and any complaint or disciplinary history. Always verify the license number on the contract matches the name and address on the CSLB record. An "active" status with no disclosures and a current bond is the minimum bar. Any "suspended" or "revoked" history is a hard stop.

What's the difference between a Class A, B, and C contractor license?

Class A is for general engineering (highways, bridges, utilities). Class B is for general building contractors who manage at least two unrelated trades on a project. Class C covers 42 specialty trades — roofing (C-39), electrical (C-10), plumbing (C-36), HVAC (C-20), and so on.

Can an unlicensed contractor work in California?

No. California law (B&P Code §7028) makes it a misdemeanor for anyone to perform contracting work valued at $500 or more without an active CSLB license. Unlicensed contractors also cannot sue to collect payment, and homeowners can recover all money paid.

How much should a contractor deposit be in California?

California law caps the down payment on a home improvement contract at 10% of the contract price or $1,000, whichever is less (Business & Professions Code §7159). Any contractor demanding more is violating state law. The cap applies to the initial deposit only. Progress payments after work starts must be tied to completed milestones and cannot exceed the value of work performed plus materials delivered to the site.

What must a California home improvement contract include?

Under B&P Code §7159, every home improvement contract over $500 must include the contractor's name/address/license number, a complete scope of work, total price, payment schedule, start and completion dates, a three-day right to cancel, and the CSLB notice and mechanics lien warning — in writing, signed before work begins.

What is a change order?

A change order is a written amendment to a construction contract that documents a change in scope, price, or schedule. In California it must be signed by both parties before the changed work begins — verbal change orders are not enforceable and are a leading source of disputes.

What insurance should a contractor have?

At minimum: $1M general liability insurance and workers' compensation coverage for every employee on site. For larger projects, also require commercial auto and an umbrella policy. Always demand a Certificate of Insurance (COI) naming you as additionally insured.

What is a contractor's bond and how much is it in California?

California requires every licensed contractor to post a $25,000 surety bond with the CSLB. The bond protects consumers, employees, and subcontractors against financial loss from license-law violations — but it's a low ceiling, so the bond alone is not adequate financial protection on a large job.

Why do I need a Certificate of Insurance from my contractor?

A Certificate of Insurance (COI) proves the contractor's general liability and workers' comp policies are active on the day work starts. Without one, you have no recourse if a worker is injured on your property or a subcontractor damages your home — claims fall back on your homeowner's policy. Always require the COI directly from the insurance broker, not the contractor, and ask to be listed as the certificate holder so you're notified if the policy lapses mid-project.

What is a mechanics lien?

A mechanics lien is a legal claim recorded against your property by a contractor, subcontractor, or supplier who hasn't been paid for work performed or materials provided. In California, a recorded lien clouds your title and can force a sale of the property if not resolved. Even if you paid your general contractor in full, an unpaid subcontractor or material supplier can record a lien against your home. That's why lien waivers and Preliminary Notices matter.

How do I prevent a mechanics lien on my property?

Require a conditional or unconditional lien waiver from your general contractor and every subcontractor or supplier who served a Preliminary Notice, signed at each progress payment. Pay only against signed waivers — no waiver, no check.

What is a Preliminary Notice (20-day notice) in California?

A California Preliminary Notice is a document that subcontractors and material suppliers must serve on the property owner within 20 days of first furnishing labor or materials to preserve their right to file a mechanics lien. Receiving one is normal — it's not a lien, just a heads-up.

What is a typical contractor payment schedule in California?

A safe payment schedule ties draws to completed milestones — never to the calendar. A common pattern: 10% deposit (or $1k cap), 20% at rough framing/demo complete, 25% at rough mechanicals, 25% at drywall, 15% at substantial completion, 5% retention released after final punch list and lien waivers.

What is contractor overhead and profit (O&P)?

Overhead and profit (O&P) is the markup a general contractor adds on top of direct costs (labor, materials, subcontractors) to cover business operations and profit margin. In Los Angeles, typical O&P runs 15–25%; markups above 25% should prompt line-item questions.

Can a contractor charge for an estimate in California?

Yes — California has no law prohibiting contractors from charging for estimates. Many reputable contractors charge a fee for detailed estimates on complex projects because producing one takes real engineering time. Free estimates are common for straightforward residential work.

How many contractor bids should I get?

Get three apples-to-apples bids from licensed contractors working off the same detailed scope of work. Fewer than three gives you no benchmark; more than four wastes everyone's time and can damage your relationships with the contractors you're seriously considering.

What red flags should I watch for in a contractor bid?

Major red flags: a deposit over 10% or $1,000, no license number on the bid, vague scope ("labor and materials to remodel kitchen"), no payment schedule tied to milestones, no proof of insurance, prices 20%+ below other bids, and pressure to sign today.

Knowledge Base

California Contractor FAQ

Direct, no-fluff answers to the questions homeowners ask before signing a contract. Every answer cites California law where it applies.

Licensing & Verification

What is a CSLB license?
How do I verify a contractor's license in California?
What's the difference between a Class A, B, and C contractor license?
Can an unlicensed contractor work in California?

Contracts & Deposits

How much should a contractor deposit be in California?
What must a California home improvement contract include?
What is a change order?

Insurance & Bonding

What insurance should a contractor have?
What is a contractor's bond and how much is it in California?
Why do I need a Certificate of Insurance from my contractor?

Liens & Legal

What is a mechanics lien?
How do I prevent a mechanics lien on my property?
What is a Preliminary Notice (20-day notice) in California?

Costs & Payments

What is a typical contractor payment schedule in California?
What is contractor overhead and profit (O&P)?
Can a contractor charge for an estimate in California?

Hiring & Vetting

How many contractor bids should I get?
What red flags should I watch for in a contractor bid?