California R&D Tax Credit 2026: What You Need to Know

Does your California business qualify for the R&D tax credit?

The California research credit derives from IRC Section 41, adapted with state modifications. The most important California-specific rule: qualifying research activities and the QREs that fund them must occur within California. Research conducted in another state does not count toward your California credit, even if it qualifies federally.

To determine whether your activities qualify, the FTB applies a four-part test:

Permitted purpose. The research must be intended to develop or improve a business component (product, process, software, technique, formula, or invention).
Technological in nature. The activity must rely on principles of physical, biological, computer, or engineering science.
Elimination of uncertainty. You must be trying to discover information that eliminates technical uncertainty about the capability, method, or design of the component.
Process of experimentation. You must evaluate one or more alternatives through modeling, simulation, systematic trial and error, or similar methods.

The four-part test catches more businesses than most owners expect. A laundromat testing new wash-cycle parameters to reduce chemical use while maintaining cleaning performance can qualify. A pet care business developing a proprietary intake or treatment protocol may qualify if the process involves genuine technical uncertainty and documented experimentation. Software modules built for internal operations qualify when the development process satisfies all four parts. The credit is not reserved for labs or tech firms.

Pro Tip: Document the uncertainty and the experimentation process in real time. Missing contemporaneous records is the most common reason California R&D credit claims fail on audit.

What calculation methods are available, and what are the rates?

California offers two methods for computing the research credit, and the FTB’s published rates are straightforward:

Regular credit: 15% of QREs that exceed a computed base amount, plus 24% for qualifying basic research payments.
ASC: 3% of QREs that exceed 50% of the average QREs for the three preceding taxable years. If you have no prior-year QREs, the start-up rate is 1.3%.

The regular credit uses a fixed-base percentage derived from historical gross receipts and QREs, which can produce a larger credit for businesses with a long, stable research history. The ASC, conformed to federal law by SB 711 effective for tax years beginning on or after January 1, 2025, uses only the prior three years of QREs as its base. That makes it more accessible for newer businesses or those with volatile spending patterns.

Dimension	Regular Credit	ASC (post-2025)
Qualifying activities	Same four-part test; CA nexus required	Same four-part test; CA nexus required
Calculation method	15% × (current QREs minus base amount)	3% × (current QREs minus 50% of 3-yr avg QREs)
Credit rate	15% (24% for basic research payments)	3% (1.3% start-up rate)
Base computation	Fixed-base % × avg gross receipts (historical)	50% of average QREs for prior three tax years
Carryforward	Indefinite	Indefinite
Election requirement	Affirmative on timely original return	Affirmative on timely original return

California does not conform to every federal change. The state’s IRC conformity date moved to January 1, 2025 under SB 711, but California retains its own in-state nexus requirement and has not adopted certain federal Section 174 capitalization changes in the same way. Always verify current conformity status with the FTB or a qualified tax professional before filing.

Pro Tip: Taxpayers with volatile historical QREs often find the ASC produces a larger credit because the three-year rolling base is lower than the fixed-base percentage used in the regular method. Run both before you commit.

How do you calculate the California research credit?

The calculation differs by method, but the inputs are the same: your California QREs for the current year and, for the regular credit, your historical gross receipts and QRE data.

Regular credit: step by step

Identify current-year California QREs. Include wages for qualified services, supplies used in research, and 65% of contract research expenses paid to non-employees.
Compute your fixed-base percentage. Divide total QREs for the base period (1984–1988 for most established businesses) by gross receipts for the same period. New businesses use a start-up formula.
Calculate the base amount. Multiply the fixed-base percentage by the average of your gross receipts for the four preceding tax years.
Apply the 50% floor. The base amount cannot be less than 50% of your current-year QREs. If your computed base exceeds that floor, use the computed base; if not, use 50% of current QREs.
Compute the credit. Multiply the excess of current QREs over the base amount by 15%.

ASC: step by step

Calculate average QREs for the prior three taxable years. Add QREs for years one, two, and three, then divide by three.
Apply the 50% floor. Multiply that average by 50%.
Compute the excess. Subtract the 50% average from current-year QREs.
Apply the 3% rate. Multiply the excess by 3% (or 1.3% if no prior-year QREs exist).

Worked example

Input	Amount
Current-year CA QREs	a representative amount
Fixed-base percentage (regular)	a representative rate
Average gross receipts (4 prior years)	a representative amount
Average QREs (prior 3 years, ASC)	a representative amount

Regular credit computation:

Computed base: 16% × $2,000,000 = $320,000
50% floor: 50% × $500,000 = $250,000
Base used: $320,000 (higher than the floor)
Excess QREs: $500,000 minus $320,000 = $180,000
Regular credit: 15% of the excess QREs equals this method’s calculation result

ASC computation:

50% of average prior QREs: 50% × $400,000 = $200,000
Excess QREs: $500,000 minus $200,000 = $300,000
ASC: 3% of the excess QREs equals this method’s calculation result

In this profile, the regular credit yields a higher credit amount than the ASC. Flip the inputs so the fixed-base percentage is high or the prior three-year QRE average is low, and the ASC can come out ahead. That is exactly why you model both before electing.

Note on the 50% floor: The floor in the regular credit calculation can materially reduce eligible QREs. Always compare your computed base to the 50% floor before finalizing the regular credit figure to avoid overstating the result.

How do carryforward rules and the $5M cap affect your credit?

The California research credit is not refundable. If the credit exceeds your tax liability in a given year, the unused balance carries forward indefinitely. There is no expiration date on carryforward credits, which makes the credit valuable even for businesses with low current-year tax liability.

One significant planning constraint applies right now. For taxable years beginning on or after January 1, 2024 and before January 1, 2027, California limits the total business credits a taxpayer can apply in a single year to $5,000,000. For businesses filing combined reports, the cap applies at the group level. Credits that cannot be applied due to this cap carry forward to future years.

Pass-through entities complete Form FTB 3523 at the entity level, then allocate the credit to owners via Schedule K-1. Individual owners apply the credit on their personal California returns, subject to their own tax liability and the applicable limitation rules.

Entity type	Completes FTB 3523?	Credit flows to
S corporation	Yes	Shareholders via Schedule K-1
Partnership / LLC	Yes	Partners/members via Schedule K-1
C corporation	Yes	Applied directly on Form 100
Fiduciary	Yes	Beneficiaries per allocation

Credits apply to the earliest taxable year possible to maximize time value.
The $5M cap does not eliminate credits; it defers them into the carryforward pool.
Individual owners receiving pass-through credits should coordinate with their personal tax preparation to confirm the limitation formula is applied correctly.

Pro Tip: Build a carryforward tracker in your year-end tax model. Under the $5M cap window (2024–2026), credits can pile up faster than they are applied, and losing track of the balance is a common and costly oversight.

How do you claim the credit on your California return?

The filing process is specific. Getting it wrong, especially on the election, can cost you the credit for the year.

Form FTB 3523 is the mandatory schedule for computing and claiming the California research credit. Attach it to your California return based on your entity type:

Form 100 (C corporation)
Form 100S (S corporation)
Form 565 (partnership)
Form 568 (LLC)
Form 541 (fiduciary/estate)

Election rules and timing. For tax years beginning on or after January 1, 2025, you must make an affirmative election between the regular credit and the ASC on your timely filed original return. You cannot make or change the election on an amended return. If you previously elected the Alternative Incremental Credit (AIC), that election does not carry forward. You must elect either the regular credit or the ASC on your 2025 return.

Filing checklist:

Completed Form FTB 3523 with all QRE schedules
Payroll allocations by project and employee showing California activity
Contract research agreements and invoices
Schedule K-1 allocation details (pass-through entities)
Documentation supporting the four-part test for each qualifying project
Written election of method (regular or ASC)

Pro Tip: If your historical QRE pattern is complex or you previously elected the AIC, file an extension to allow time for proper modeling. An extension gives you more time to file, not more time to pay, but it does preserve your ability to make the election on the original return.

Check upcoming tax deadlines before scheduling your modeling work so the election lands on a timely return.

What records do you need to survive an audit?

Documentation is where most California R&D credit claims succeed or fail. The FTB can audit credits years after filing, and memory-based reconstructions rarely hold up.

Essential records to maintain:

Project descriptions stating the business component being developed and the technical uncertainty involved
Contemporaneous timekeeping records tied to specific California research activities, by employee
Payroll allocations showing the percentage of each employee’s time spent on qualified research
Invoices and contracts for third-party research, with evidence the work occurred in California
Design notes, test plans, test results, and change logs
Source code repositories with commit histories (for software development projects)
Technical memos documenting the process of experimentation and what alternatives were evaluated

Common pitfalls:

Documenting only the outcome, not the experimentation process
Failing to show California nexus for each QRE (research performed outside the state does not qualify)
Relying on year-end summaries instead of contemporaneous records
Claiming wages for employees who performed routine data collection or quality control rather than qualified research

A bookkeeping provider can generate or tag several of the supporting documents automatically: timesheets coded to project, payroll journals by department, and supplier invoices linked to research contracts. That is one reason keeping bookkeeping and tax under one roof reduces audit exposure.

Pro Tip: Set up a dedicated project folder for each qualifying activity at the start of the year. Populate it in real time. Reconstructing documentation 18 months later, under audit notice, is expensive and often incomplete.

What changed with SB 711, and what should you do now?

SB 711 is the most significant change to California’s research credit in years. Effective for tax years beginning on or after January 1, 2025, California conformed to the federal ASC under IRC Section 41, and simultaneously repealed the Alternative Incremental Credit (AIC).

The practical impact is direct. Taxpayers who previously elected the AIC must make an affirmative election of either the regular credit or the ASC on a timely filed original return for tax years beginning on or after January 1, 2025. There is no default. Missing that election is a compliance problem with real dollar consequences.

Planning checklist for 2025 and 2026 returns:

Pull your QRE records for 2022, 2023, and 2024 to build the ASC base calculation.
Model the regular credit and the ASC under at least two spending scenarios (flat QREs and 20% growth).
If you previously elected the AIC, confirm with your tax preparer that the new election is made on the original return.
Review whether any research activities shifted in or out of California during the year since nexus attribution affects both methods.
Update internal reporting systems to tag California-specific research expenses separately from federal QREs.

The ASC is particularly worth modeling for businesses that lack the long historical records needed to compute a favorable fixed-base percentage. A rolling three-year QRE average is easier to document and often produces a competitive credit for growing businesses.

Pro Tip: Maintain a rolling three-year QRE summary as a standing document in your tax file. It makes ASC modeling fast and gives you a defensible starting point if the FTB asks questions.

For deeper planning around the election and its long-term effects, California tax strategies should account for the binding nature of the choice across multiple future years.

Key Takeaways

California’s research credit requires an affirmative election between the regular credit and the ASC on a timely filed original return, and that election is binding under post-2025 rules established by SB 711.

Point	Details
Two methods, one binding election	You must elect the regular credit (15%) or ASC (3% or 1.3% start-up rate) on your timely original return; no default applies post-2025.
California nexus is required	QREs qualify only for research activities conducted within California; out-of-state work does not count.
$5M cap through 2026	Credits are capped at $5,000,000 per year for 2024–2026; unused credits carry forward indefinitely.
Documentation wins audits	Contemporaneous project memos, timesheets, and payroll allocations are the records that hold up under FTB review.
Tolliver Bookkeeping and Tax	Tolliver models both credit methods, prepares Form FTB 3523, and maintains the bookkeeping records that support your claim.

The election is the part most businesses get wrong

Most articles about the California R&D tax credit spend their energy on rates and eligibility. Those matter, but the binding election is where real money gets left on the table or lost entirely.

Before SB 711, many California businesses defaulted to the AIC because it was simpler to compute. That option is gone. Now every taxpayer must affirmatively choose between two methods with meaningfully different outcomes depending on their QRE history, and they must make that choice before the original return deadline. An amended return cannot fix a missed or wrong election without FTB consent, which is not guaranteed.

The other thing practitioners see repeatedly: businesses that qualify and never claim. Process improvements in laundromat operations, proprietary care protocols in pet businesses, custom software built for internal workflows. These are not exotic R&D projects. They are the kind of work that satisfies the four-part test when it is documented correctly. The credit exists for exactly these businesses, not just biotech firms in San Diego.

The combination of a binding election, a temporary $5M utilization cap, and the new ASC option means the 2025 and 2026 returns are unusually consequential. Getting the modeling right before you file is not optional planning. It is the whole game.

How Tolliver Bookkeeping and Tax can help you claim this credit

Claiming the California research credit correctly requires three things working together: clean books that capture QREs by project, a tax preparer who can model both methods and make the right election, and documentation that holds up if the FTB asks questions. Tolliver Bookkeeping and Tax provides all three from one office in Bakersfield, serving Kern County businesses for over two decades.

Services relevant to R&D credit claims include monthly bookkeeping structured to tag California QREs by project, business tax preparation including Form FTB 3523 preparation and election advisory, tax planning engagements that model regular credit versus ASC outcomes under multiple scenarios, and FTB representation if your credit is questioned. As a Xero Silver Partner, Tolliver sets up your books to capture the project-level data the FTB expects, and clients share documents securely through the Client Hub portal.

Laundromat owners and pet business operators are welcome to ask specifically about qualifying activities in their industries. Both sectors have more qualifying activity than most owners realize.

To start a modeling consultation, visit tollivercpa.com/pricing or reach out directly at 5401 Business Park S., Suite 126, Bakersfield.

Useful sources

The sources below are the primary references for California R&D credit rules, forms, and recent legislative changes.

California Research Credit overview, FTB.ca.gov: The FTB’s official summary of credit rates, eligibility, and conformity status. Start here for the current rate table and a plain-language overview.
2025 Instructions for Form FTB 3523, FTB.ca.gov: The authoritative source for ASC mechanics, election rules, and line-by-line computation guidance for tax years beginning on or after January 1, 2025.
2024 Instructions for Form FTB 3523, FTB.ca.gov: Covers the $5M credit limitation, pass-through allocation rules, and form attachment requirements.
California Revenue and Taxation Code Section 23609, leginfo.legislature.ca.gov: The statutory text establishing California’s research credit and its tie to IRC Section 41. Use this for the governing law.
SB 711 bill text, leginfo.legislature.ca.gov: The full text of the 2025 conformity legislation, including the ASC adoption and AIC repeal provisions.
California R&D tax credit changes as IRC conformity advanced, RSM US: Practitioner-level analysis of SB 711’s impact, election binding rules, and planning implications. Best source for modeling guidance.
Form FTB 3523 glossary and practice notes, SwansonReed: Useful for understanding nexus requirements, the 50% floor rule, and documentation expectations.

This article provides general information about California tax law and is not a substitute for professional tax advice. Consult a qualified tax professional or the FTB directly to confirm current rules and how they apply to your specific situation.

FAQ

Who qualifies for the California R&D tax credit?

Any California business that conducts qualified research activities within California may qualify. The activity must satisfy the four-part test: it must have a permitted purpose, be technological in nature, address genuine technical uncertainty, and involve a process of experimentation.

How do you calculate the California R&D tax credit?

Under the regular method, the credit equals 15% of QREs that exceed a base amount computed from your historical fixed-base percentage and gross receipts. Under the ASC, the credit equals 3% of QREs that exceed 50% of your average QREs for the prior three taxable years (1.3% if you have no prior-year QREs).

What are the new R&D tax credit rules for California in 2026?

SB 711 repealed the Alternative Incremental Credit and conformed California to the federal ASC, effective for tax years beginning on or after January 1, 2025. Taxpayers must now make an affirmative election between the regular credit and the ASC on a timely filed original return; there is no default method.

What is the 80% rule for the R&D credit?

A federal rule under IRC Section 41 limits the qualifying wages of an employee who both supervises and directly performs qualified research, and California generally follows this rule as part of its conformity to IRC Section 41.

Can Tolliver Bookkeeping and Tax help with Form FTB 3523?

Yes. Tolliver Bookkeeping and Tax prepares Form FTB 3523, models both the regular credit and the ASC, and maintains the bookkeeping records needed to support a California research credit claim for Kern County businesses.