California Change Order Payment Disputes & SB 440 Attorney

The “build now, fight later” problem

Change orders are where large private projects most often go sideways. A contractor is directed to perform extra or changed work, the owner disputes or sits on the request, and — under the old norm — the contractor was pushed to keep building under protest and sort out payment at the end, absorbing the cash-flow hit in the meantime. That dynamic favored whoever held the money.

Effective January 1, 2026, SB 440 changes the rules for qualifying private-works contracts by importing a structured claims process, long available on public works, into private construction.

How the SB 440 claims process works

The statute sets a sequence with firm deadlines:

Written claim — the contractor or, through the contractor, a subcontractor submits a documented claim for payment or a time extension by registered or certified mail.
30-day owner response — the owner must review and respond in writing within 30 days, identifying what is disputed and undisputed. Failing to respond is treated as a denial that moves the process forward.
Meet-and-confer, then mediation — if the contractor contests the response, it can demand a conference within 30 days, followed by a further written statement; unresolved disputes proceed to non-binding mediation.
Payment and interest — undisputed amounts must be paid within 60 days, and late payment accrues interest at two percent per month (24 percent annually) on what was wrongfully withheld.

Stop-work rights you cannot sign away

The most significant shift is leverage. If an owner ignores the statutory timelines or refuses to mediate, SB 440 gives the contractor the right to suspend work without penalty or liability for the resulting delay. And the statute makes its protections non-waivable: a contract clause that tries to waive them is void as against public policy. For contractors, that converts a slow change-order fight into an enforceable right to be paid or to lawfully stop.

Scope and timing

SB 440 applies to qualifying private-works contracts entered into on or after January 1, 2026, and is set to sunset January 1, 2030 unless extended. It does not apply to certain smaller residential projects or to public-entity owners, and it supplements — rather than replaces — existing prompt-payment, lien, and stop-notice remedies. Whether a given claim qualifies, and how to invoke the process correctly, turns on the contract date and on following the statute’s notice mechanics precisely.

The statute

Private Works Change Order Fair Payment Act: Civ. Code §§ 8850–8859 (SB 440), effective Jan. 1, 2026, applicable to contracts entered into on or after that date; set to sunset Jan. 1, 2030. Excludes certain small residential projects and public-entity owners.

How Stone LLP applies SB 440

Because the law is new, the procedural details matter — the method of service, the documentation, and the deadlines all affect whether the leverage is available. Stone LLP integrates SB 440 claims with prompt-payment penalties and the firm’s other collection tools. With 45 years representing California businesses from Irvine, Century City, and San Jose, the firm focuses on substantial private-works disputes.

Call 949-477-9100

Frequently asked questions

What is SB 440?

It is California’s Private Works Change Order Fair Payment Act, codified at Civil Code sections 8850 and following, effective January 1, 2026. It creates a mandatory claims process for change-order and time-extension disputes on qualifying private projects.

Which projects does SB 440 cover?

Qualifying private-works contracts entered into on or after January 1, 2026. It generally excludes certain smaller residential projects and contracts where the owner is a public entity.

Can a contractor really stop work under SB 440?

Yes. If an owner fails to meet the statute’s deadlines or refuses mediation, the contractor may suspend work without penalty for the resulting delay. These rights cannot be waived by contract.

What interest applies to late change-order payments?

Undisputed amounts not paid within the statutory window accrue interest at 2 percent per month — about 24 percent per year — on the wrongfully withheld sum.

Does SB 440 replace my lien and prompt-payment rights?

No. It adds a change-order claims process on top of existing remedies; liens, stop notices, and prompt-payment penalties remain available. Call 949-477-9100 to discuss how they fit together.