Checking a Contractor’s License Before Hiring

Why a License Check Is the First Thing You Do — Not the Last

The most expensive mistake in residential construction rarely looks like a mistake when it's happening. It looks like a friendly guy with a great portfolio and a neighbor's endorsement — and it can cost you a quarter of a million dollars or more.

In California, the law draws a hard line: any project valued at $1,000 or more in combined labor and materials requires a licensed contractor, per the CSLB's official rules on illegal contracting. Unlicensed individuals may not bid on jobs exceeding $500. If you're planning a ground-up custom home, a whole-home renovation, or an ADU in Altadena, you're not near that line — you're miles past it.

The stakes are not theoretical. A 10News investigation documented one household that lost an estimated $250,000 and sold a gutted house at a loss, while another family faced a $600,000+ estimate just to finish their home. In several of those cases, a free CSLB license lookup would have exposed the problem in under five minutes — before a single dollar changed hands.

Here's what homeowners too often treat as verification when it isn't:

• A charming personality and a beautiful portfolio — these win you over, but they aren't substitutes for official qualifications.
• A neighbor's referral — the neighbor was charmed by the same person.
• A verbal assurance that "everything is licensed and insured" — ask for the number and check it yourself.
• A "project manager" title — CSLB states anyone who oversees or supervises a project is functioning as a contractor under California law.

A real license means something. Every licensed contractor in California has submitted fingerprints for a criminal background check before their license was issued, as CSLB Registrar David Fogt has stated publicly. Licensed contractors carry bonds and insurance, and they answer to a state regulator with the power to discipline them — which gives them real incentive to play fair.

That's why at JMB Builders, our license number — CSLB #1103479 — goes into every first conversation, before we ever talk scope or budget. Homeowners can look it up on the CSLB site and see the active status, the classification, and the bond on file for themselves. We'd rather you verify us than take our word for it.

Run the license check first, before you fall in love with a bid. Once someone has your deposit and your trust, you're negotiating from weakness. Before the contract, take ten minutes: look up the license, confirm the business name on the license matches the contract, and if a potential hire is reluctant to share their license number, treat that as the red flag it is. Charm is free. Verification is free. Only one of them protects you.

The 5-Minute CSLB License Lookup: What to Check Beyond 'Active'

Finding "Active" next to a contractor's license number feels reassuring, but it's only the first box to check. A license can be active, legitimate, and still wrong for your project — and that mismatch can cost you far more than a bad hire.

Start at the CSLB's free "Check a License" tool, which the board offers specifically to help homeowners verify contractors before signing anything. Confirm the status is active, then dig into the full record. Experts recommend reviewing the license's classification, renewal history, and any complaints or disciplinary actions — repeated renewal lapses, for instance, can signal disorganization, and anything other than "active" status is a deal-breaker (practical verification guidance).

Classification matters more than most homeowners realize. A B-General Building license covers broad residential construction, while specialty classifications cover narrower scopes like roofing or electrical. Hiring someone to work outside their licensed specialty can void your homeowner's insurance — a devastating discovery only after something goes wrong (same source). For a ground-up custom home, full rebuild, or ADU in Altadena, you need a general contractor whose classification genuinely matches the entire scope, not just part of it.

Then check the paperwork details:

• Confirm the business name on the license matches the name on your contract exactly — a mismatch creates real problems if a dispute arises.
• Review the record for complaints or disciplinary actions, not just the issue date.
• Note the renewal history; a long, continuous record suggests a stable, established business.
• Have the insurer send your certificate of insurance directly to you, and call the surety to confirm the bond is current (contractor verification checklist).

This diligence takes minutes, and the stakes justify it. In one investigation, homeowners lost between $250,000 and $600,000 to unlicensed operators — losses that a simple license lookup would have exposed early (10News investigation). California requires a licensed contractor for any project valued at $1,000 or more, so virtually any real renovation or build falls squarely under licensing law (CSLB).

At JMB Builders, we encourage every Altadena homeowner to run this check on us before signing anything. Our license (#1103479) is active in the B-General Building classification, our $2,000,000 general liability policy and $100,000 contractor bond are on file, and the name on our license is the name on our contracts. A contractor confident in their record welcomes the lookup — reluctance to share a license number is a major red flag.

Verify Insurance and Bonds Directly — Don't Take the Contractor's Word

A certificate of insurance folded into a proposal packet tells you almost nothing — paper can be outdated, altered, or simply fake. The only document that counts is the one that arrives directly from the insurance company, addressed to you.

Ask the contractor for the name and phone number of their insurance agent, then call and request that the insurer send the certificate of insurance directly to you, not through the contractor. This is standard practice among reputable builders — at JMB Builders, we expect homeowners to verify our $2,000,000 liability coverage this way, and a contractor who bristles at the request is telling you something. Practical hiring guidance is clear on this point: have the insurer send the certificate straight to the homeowner and call the surety company to confirm the bond is current.

Do the same with the surety bond. A bond number means nothing until the surety confirms it's active, in the correct business name, and sufficient for your project's scope. Ten minutes on the phone closes the gap between "he said he's bonded" and actual, enforceable protection.

Skipping these steps exposes you to three risks most homeowners never see coming:

• Injury liability. If an uninsured worker gets hurt on your property, you can be held liable for their injuries.
• No insurance coverage for the work itself. Most homeowner policies exclude damage from unlicensed or improperly licensed work — you absorb the loss personally.
• Subcontractor and supplier liens. Unpaid subs and material suppliers can place liens on your home even if you paid the contractor in full.

These aren't theoretical. Government building departments warn that homeowner policies typically provide no coverage for unlicensed work, and that liens from subcontractors and suppliers can attach to your property when the person you hired never had proper credentials in place. The stakes scale with the project — a ground-up home or whole-home renovation in Altadena represents hundreds of thousands of dollars, far above California's $1,000 threshold at which a licensed contractor is legally required.

Verification is also a filter that works in both directions. A builder doing legitimate, high-end work — custom homes, rebuilds, ADUs — has nothing to hide and every reason to make this easy for you. The ones who resist direct verification are screening themselves out of your project, which is exactly what you want.

Red Flags That Should End the Conversation

Some red flags don't whisper — they end the conversation on the spot. If a contractor dodges your license question or asks for a big check upfront, you're not being cautious by walking away. You're doing exactly what state regulators would tell you to do.

Take the so-called "project manager" loophole. Some unlicensed operators claim they don't need a license because they're "managing" the project, not building it. CSLB spokesman Rick Lopes dismantled that argument on the record: "The law defines what a contractor is and one of the things it says is it's someone who can oversee or supervise a project. A project manager oversees or supervises a project." In other words, the title changes nothing — anyone supervising your build is a contractor under California law.

Another deal-breaker is hesitation when you ask for a license number. Verification experts put it plainly: if a potential hire is reluctant to share their number, consider it a major red flag. Licensed contractors — JMB Builders among them, carrying CSLB License #1103479 — hand that number over without a second thought, because it's how homeowners confirm active status, classification, and history.

Then there's the money. California caps down payments at the lesser of 10% of the project cost or $1,000, and violations carry fines up to $5,000 and/or up to a year in county jail. If someone demands half the project cost upfront, that's not a deposit — it's a warning. During a two-day CSLB sting in Campbell, 6 of 14 individuals cited for illegal contracting demanded excessive down payments, and one had a prior grand theft conviction.

The stakes aren't hypothetical. In a 10News investigation, one victim discovered the contractor she'd hired had convictions for grand theft, fraud, forgery, and bad checks in California and Florida — but only by running a simple Google search of his name, and only after losing money. That search takes five minutes. Do it before you sign anything, not after.

When you're evaluating builders for a ground-up home, a whole-home renovation, or an ADU in Altadena, treat these signals as non-negotiable:

• Refuses to provide a license number or tells you licensing doesn't apply to their role
• Requests a down payment above California's 10%/$1,000 cap
• Claims to be a "project manager" or "consultant" rather than a contractor
• Fails to disclose in writing that they're unlicensed when advertising construction services

A charming personality and a beautiful portfolio can win you over, but they aren't substitutes for official qualifications. Any legitimate builder will welcome your verification — and if one bristles at the question, you already have your answer.

What Full Verification Looks Like on a Real Altadena Project

A license number printed on a business card proves nothing — what matters is what the state's records actually say. So let me show you what full verification looks like on a real Altadena project, using our own credentials as the example.

When an Altadena homeowner hires us at JMB Builders for a ground-up home, rebuild, whole-home renovation, or ADU, the first thing they can check is our CSLB License #1103479. California requires a licensed contractor for any project valued at $1,000 or more in combined labor and materials, or any project requiring a building permit — a threshold every major residential project clears by orders of magnitude, per the CSLB's official guidance. A free lookup on the CSLB site confirms the license is active, the classification matches the scope, and the business name on the license matches the name on the contract.

But "active" status is only the start. Experts recommend reviewing the full license record — classification, renewal history, and any complaints or disciplinary actions — because hiring outside a contractor's licensed specialty can void your homeowner's insurance, according to licensing verification guidance. Here's what a homeowner should expect to see before signing a contract for large-scope work:

• An active CSLB license, with the number printed directly on the contract
• General liability insurance verified with the insurer directly — ours is $2,000,000 in coverage
• A current contractor bond confirmed with the surety — ours is a $100,000 bond on file
• A down payment within California's legal cap of 10% of project cost or $1,000, whichever is less

That down payment cap matters more than most homeowners realize. In a July 2024 CSLB sting in Santa Clara County, 14 individuals were cited for illegal contracting, and 6 of them demanded excessive down payments — violations that carry fines up to $5,000 and potential jail time, as CSLB enforcement records show. Licensed contractors also submit fingerprints for a criminal background check before their license is issued, which is vetting an unlicensed operator simply doesn't have.

Verification is the cheapest insurance you'll ever get. It takes ten minutes on a free state website, and it can be the difference between a completed home and the documented losses seen in unlicensed cases — some homeowners lost $250,000 or more. If you're planning a project in Altadena and want to talk through scope, budget, and fit, call us at (310) 491-6878 for a free, no-commitment consultation.