Are Time and Materials Contracts Legal in California?

Time and materials contracts are legal in California for commercial, industrial, and government work, but they are effectively prohibited on residential home improvement projects. Business and Professions Code Section 7159 requires every home improvement contract to state a fixed price in dollars and cents, which an open-ended hourly billing arrangement cannot satisfy. On commercial and public jobs the arrangement remains a standard tool, subject to careful drafting around labor rates, materials, ceiling prices, and documentation.

Why Residential Home Improvement Work Can’t Use T&M

The residential rule turns on a single statutory line. Section 7159 requires every home improvement contract to include a heading labeled “Contract Price” followed by the total amount in dollars and cents.¹ A T&M arrangement, where the final cost depends on hours worked and materials consumed, cannot produce that number at signing.

The rule applies broadly. A “home improvement contract” under Section 7159 covers work on any existing residential property once the total price for labor, services, and materials exceeds $500.¹ Kitchen remodels, bathroom renovations, roof replacements, additions, landscaping overhauls. If the work touches an existing home and costs more than $500, the contractor needs a fixed contract price. Labeling the deal something else does not create a workaround.

The statute also controls how money moves during the project. Down payments are capped at $1,000 or 10 percent of the contract price, whichever is less. Progress payments must be tied to specific phases of completed work and stated in dollars and cents, and a contractor cannot collect payment for work not yet performed or materials not yet delivered.¹ Every dollar between owner and contractor has to trace back to defined work at a defined price.

Service and Repair Calls Follow the Same Rule

Section 7159.5 governs service and repair work separately from full remodels, but the pricing rule is identical: the contract must state the agreed amount in dollars and cents, covering profit, labor, and materials.² Even a service call to diagnose a plumbing leak or repair an appliance needs a stated total price rather than an open hourly rate.

Service and repair contracts carry the same $1,000 or 10 percent down payment cap and the same prohibition on billing ahead of completed work.² A contractor who wants flexibility on a service call should give a written estimate for the likely scope, then use a change order if the problem turns out bigger than expected.

Change Orders Are the Residential Workaround

Because T&M pricing is off the table for residential work, change orders are the mechanism California law provides when scope shifts after signing. A change order must be in writing and signed by both parties before the new work begins.¹ Each one needs three elements: a description of the extra work, the dollar amount added to or subtracted from the contract price, and how the change affects the payment schedule or completion date.

The original contract itself must include a notice telling homeowners they are not required to authorize extra work without a written change order, and that any change order missing the required details is unenforceable against them.¹ Contractors used to T&M billing on commercial jobs tend to trip up here. Verbal agreements to “just handle it” do not create enforceable obligations, however reasonable the extra charges look.

Penalties for Billing T&M on a Home

A contractor who bills T&M on a home improvement project faces trouble on several fronts at once. The Contractors State License Board can bring disciplinary action for failing to comply with any provision of Section 7159, up to suspension or revocation of the license.¹

Criminal exposure is real. Violating the pricing, down payment, or payment-for-unperformed-work rules under Section 7159.5 is a misdemeanor carrying fines between $100 and $5,000, up to one year in county jail, or both.² When the violation occurs in an area where the Governor has declared a state of emergency, the court must impose the maximum fine. Working without a valid license at all is a separate misdemeanor, punishable on a first offense by up to $5,000 in fines and six months in jail.³

The contract itself is at risk too. California courts have held that home improvement contracts violating Section 7159 can be voided, though not automatically in every case. Courts consider whether the homeowner is the type of consumer the statute was designed to protect and whether voiding the deal would produce unjust enrichment. A sophisticated property owner who received substantial value from the work may have a harder time getting the contract thrown out than a first-time homeowner who was clearly taken advantage of. The statute of limitations for these violations is two years from the date the buyer signed the contract.

Where T&M Contracts Are Allowed

Outside residential home improvement, T&M is a standard tool. Commercial construction, tenant improvement projects for businesses, industrial work, and government contracts all use T&M pricing when the scope of work is genuinely uncertain at the outset. California has no statute equivalent to Sections 7159 or 7159.5 restricting T&M on these project types.

Federal government contracts performed in California follow the Federal Acquisition Regulation, which allows T&M only when the contracting officer determines that no other contract type is suitable and that the work’s extent or duration cannot be estimated accurately at award. That determination must be documented in writing before signing, and if the base period plus options exceeds three years, the head of the contracting activity must also approve it.⁴

What a Valid T&M Contract Needs

On commercial and government work where T&M is available, enforceability comes down to precise pricing terms set before the job starts. Vague language about “reasonable rates” or “cost plus markup” invites the kind of disputes that are expensive for everyone.

Labor Rates

The contract should specify a fixed hourly rate for each category of worker, bundling wages, overhead, general and administrative costs, and profit into a single all-in number.⁵ Electricians, project managers, and general laborers each get their own rate, and only workers who meet the qualifications for a given category can bill at that category’s rate. The contract shouldn’t let a general laborer bill at a journeyman electrician’s rate just because they’re on the same site.

Travel time needs explicit treatment. Ordinary commuting to and from a job site is generally not compensable under federal labor rules, but travel that is an integral part of the work itself may be. The contract should say whether travel time is billable, at what rate, and under what circumstances. Leaving this ambiguous is one of the most common sources of T&M billing disputes.

Materials Pricing

The materials clause should define exactly how the client will be charged for supplies, subcontractor costs, and other direct expenses. The two main approaches are cost-plus (actual purchase price plus a stated percentage markup) and pass-through (actual cost with no markup, where the contractor’s profit comes entirely from labor rates). Under the FAR, materials include direct supplies, incidental subcontractor services without a specified labor category, travel, and applicable indirect costs.⁵

Whatever method the parties choose has to be spelled out before the first purchase order. A contract that bills materials “at cost” without defining whether cost includes shipping, sales tax, handling, or restocking fees for returns will generate arguments.

Ceiling Prices

A ceiling price or not-to-exceed clause turns an open-ended T&M arrangement into a bounded one. The client pays actual time and material costs up to the cap, and any costs beyond that point are the contractor’s problem unless the parties execute a written change order raising the ceiling.

For federal T&M contracts a ceiling price is mandatory, and the contractor exceeds it at their own risk.⁴ The contractor must notify the government when projected costs in the next 30 days would push total spending past 85 percent of the ceiling, along with a revised cost estimate and supporting documentation.⁵ Before increasing any ceiling, the contracting officer must analyze pricing to confirm the increase serves the government’s interest and document that analysis in the contract file. On private commercial jobs a ceiling isn’t legally required, but it is strongly advisable.

Documentation and Records

T&M contracts live or die on paperwork. Because the client is paying for actual hours and actual materials rather than a fixed lump sum, every dollar billed needs a paper trail that can withstand scrutiny.

For labor, that means daily time records showing each worker’s name, classification, hours on the job, tasks performed, and the applicable hourly rate. Rounding conventions matter. A contract that bills in 15-minute increments produces different totals than one billing in full-hour blocks, so the method should be set upfront. For materials, original supplier invoices and receipts should back every charge, with any markup applied transparently under the formula in the contract.

Invoicing frequency and format belong in the contract as well. Monthly cycles are standard on longer projects; biweekly invoicing shows up on faster work. Each invoice should separate labor and materials, show the running total against any ceiling, and reference the contract provisions authorizing each charge category. The contractor carries the burden of proving billed costs were necessary and directly related to the project scope.

On any T&M arrangement of meaningful size, the client should negotiate an audit clause covering the contractor’s financial records, supplier invoices, timesheets, and subcontractor agreements. Key points to address include the scope and frequency of audits, advance-notice requirements, whether third-party auditors are allowed, how long records must be retained after project completion, and what happens if the audit turns up overbilling. Federal contracts include audit rights by default; on private commercial deals, the protection exists only if the contract creates it. In California, the limitations period for written contracts is four years, and contractors who lose the records supporting a T&M invoice within that window will struggle to defend billing disputes.

1
California Legislative Information. California Business and Professions Code BPC 7159 – Home Improvement Contracts
2
California Legislative Information. California Business and Professions Code BPC 7159.5
3
California Legislative Information. California Business and Professions Code BPC 7028
4
Acquisition.GOV. 48 CFR 16.601 – Time-and-Materials Contracts
5
Acquisition.GOV. Federal Acquisition Regulation 52.232-7 – Payments Under Time-and-Materials and Labor-Hour Contracts