How to Set Up an S Corp in California (and What It Really Costs)

The mistake is copying break-even math from a no-tax state. In California the S corp has a landlord, and the rent is 1.5%.

If you have not yet chosen your entity or you want the generic setup walkthrough, start with our step-by-step S corp setup guide. This page stays California-only: the mechanics that change once you form here.

Formation is a one-time cost. Running the entity every year afterward is not free, and California adds line items most other states do not. For the generic formation cost breakdown (state filing fees, registered agent), see our S corp setup guide. Below is what running the entity costs every year once it exists.

Screenshot-worthy summary: most owners should budget somewhere in the low four figures per year just to keep a California S corp compliant, before a single dollar of tax savings shows up.

Six filings stand between you and a compliant California S corp. Here they are in order.

1. 1. Choose and form the entity with the California Secretary of State.

   Form an LLC or a corporation. California does not allow most licensed professionals, including physicians, to use an LLC; the standard vehicle is a professional corporation that then elects S status the same way. If that is you, see the California locum tenens section below.

2. 2. Get an EIN.

   Free, online at IRS.gov, minutes to complete. You need it before Form 2553 and before payroll. Full walkthrough in our step-by-step S corp setup guide.

3. 3. File Form 2553 with the IRS.

   Deadlines and late-election relief are generic federal mechanics; see the setup guide for those. The California point: no separate state S election is required. California automatically recognizes the federal election. You still file Form 100S, the California S corp return, every year regardless.

4. 4. File the initial Statement of Information.

   New entities must file an initial Statement of Information with the Secretary of State within 90 days of formation. After that, corporations renew it every year by the last day of their anniversary month, for a $25 fee.

5. 5. Register with the California EDD and set up state payroll.

   Once you pay $100 or more in wages to an employee in a calendar quarter, you have 15 days to register as an employer with the Employment Development Department. Set up California payroll withholding, including State Disability Insurance at 1.3% for 2026, alongside your federal payroll. Unlike Social Security, California SDI has no wage cap, so it applies to every dollar of salary, not just the amount below a threshold.

6. 6. Set a reasonable salary.

   The FTB rides along with IRS reasonable-compensation standards; there is no separate California test to satisfy. Set salary by the evidence for the work performed, not by what minimizes this year's franchise tax. Our reasonable salary guide walks through how to document it.

7. 7. Calendar the ongoing California obligations.

   Form 100S, FTB estimated payments, and Statement of Information renewals all repeat every year. Put them on a calendar the same week you finish step one; missed CA filings are one of the most common cleanup projects we see.

The 1.5% franchise tax is computed on the corporation's California net income, and salary is a deductible expense to the corporation before that number is calculated. That is the key teaching point: because salary reduces the corporation's taxable income, the 1.5% tax mostly falls on the distribution slice, which is exactly the slice generating your federal payroll-tax savings. The state taxes the same dollars you are optimizing. That is why the break-even moves.

The $800 minimum applies even in a loss year, with one exception: under California Revenue and Taxation Code Section 23153(f), a newly incorporated or newly qualified corporation is exempt from the $800 minimum in its first taxable year. The 1.5%-of-net-income component can still apply in that first year if the business is profitable; the exemption covers the minimum only, not all California tax.

Estimated payment mechanics matter too: the franchise tax is paid through the year, not settled entirely at filing time, so the $800 should not surprise anyone the following April. Build it into your quarterly planning from day one.

In Texas the S corp is a discount. In California it is an investment with a management fee. Investments with fees need a bigger return to clear the hurdle.

Here is the setup: a hypothetical 1099 consultant nets $120,000 in annual profit. A reasonable salary for the work performed is set at $70,000 (illustrative; see our reasonable salary guide for how a real figure gets documented), leaving $50,000 taken as distributions.

The federal savings is the same in both states: roughly 15.3% of the $50,000 distribution slice avoids self-employment tax, since that slice is below the 2026 Social Security wage base of $184,500. After accounting for the SE-tax deduction effect and the QBI drag from moving income out of wages, the net illustrative federal savings lands around $6,500, in the $6,000 to $7,000 range cited elsewhere on this site. That number is identical whether the consultant is in Texas or California. What differs is what each state takes back out.

The same consultant nets roughly $1,200 less per year from the S corp in California than in Texas in this illustrative example, and the profit level where the S corp beats a sole proprietorship shifts up accordingly. As a rough modeling heuristic: in most no-tax states we start modeling an S corp seriously in the same range cited in our generic setup guide; in California, add roughly $15,000 to $20,000 of profit to that starting point before the math comfortably clears the franchise-tax drag. Results vary. Run your own numbers rather than anchoring on this example.

California locum tenens physicians typically need a professional corporation, not an LLC, before they can elect S status. That is the same restriction covered above, and it applies to nearly every licensed physician working through their own entity in this state.

The harder question for locums is residency. A California resident physician's income is California-source regardless of where the work happens. A nonresident physician who is based elsewhere but takes California assignments can still create California-source income and a California filing obligation from the days worked in the state, even without ever moving here. That filing exposure changes whether the California S corp overhead is worth carrying at all, versus structuring the entity in the physician's home state and handling California as a nonresident filing.

Composite hypothetical: a locum physician grossing $250,000 a year, California resident, likely clears the California-adjusted break-even from the worked example above without much debate. The same doctor based in Nevada, taking occasional California assignments, faces a different calculation entirely, weighing California nonresident filing complexity against the entity's home-state economics. Neither answer is universal; it depends on the split of days and dollars across states.

Multi-state locums should read our full locum tenens tax guide for the complete picture, and get multi-state tax filing help if you are working assignments across state lines. If you are still comparing W-2 employment to running your own S corp as a physician, our W-2 vs. S corp guide for physicians covers that decision directly.

If the S corp only wins by a few hundred dollars a year in your projection, skip it. The paperwork is not free even when the tax math technically works. For the fuller should-you-even comparison, see LLC vs. S corp.