Quick Answer

Yes, a C Corp can c corp change to s-corp in later years after its initial formation. There is no IRS rule that forces you to make the S Corp election during your first year. You can convert at any point, whether your C Corp is two years old or twenty. The catch is that the election must be filed on Form 2553 by March 15 of the year you want the S Corp status to take effect, and you must satisfy every eligibility requirement under IRC Section 1361(b). Miss the deadline or overlook a single qualification rule, and you stay locked in the C Corp tax structure for another full year, potentially costing you $20,000 to $50,000 in avoidable taxes.

The $38,700 Question Every C Corp Owner Eventually Asks

If you formed your business as a C Corporation years ago and never questioned it, you are not alone. Attorneys, online formation services, and even some CPAs default to C Corp filings because it sounds official. Nobody stops to mention that the entity you picked in year one does not need to follow you forever.

Here is the math that changes minds. A California C Corp earning $200,000 in net profit pays federal corporate tax at 21%, which is $42,000. The owner then takes the remaining $158,000 as a qualified dividend taxed at 23.8% federally (20% long-term capital gains rate plus 3.8% Net Investment Income Tax), adding $37,604. California taxes that same dividend at ordinary income rates up to 13.3%, tacking on another $16,390. The total combined tax bill lands around $95,994, an effective rate above 47%.

Now run the same $200,000 through an S Corp. The owner pays herself a reasonable salary of $80,000, subject to payroll taxes of roughly $12,240. The remaining $120,000 flows through as a distribution, avoiding self-employment tax entirely. After federal income tax, California state tax, and the 1.5% S Corp franchise tax, the total bill comes to approximately $57,300. That gap of $38,700 is real money that compounds every single year you wait.

The question is not whether a can c corp change to s-corp in later years. It absolutely can. The question is how many years of unnecessary tax you are willing to absorb before you make the switch.

Five IRS Requirements You Must Clear Before Converting

The IRS does not hand out S Corp status to every C Corp that asks. Section 1361(b) of the Internal Revenue Code sets five hard eligibility requirements. Fail any single one and your Form 2553 gets rejected.

Requirement 1: Domestic Corporation Only

Your C Corp must be organized under the laws of a U.S. state or territory. Foreign corporations are automatically disqualified. If you incorporated in Delaware but operate in California, you still qualify because Delaware is a domestic jurisdiction. However, you will need to maintain California registration and pay both states’ fees until you dissolve the out-of-state entity.

Requirement 2: 100-Shareholder Cap

S Corps cannot have more than 100 shareholders. Family members can elect to be treated as a single shareholder under IRC Section 1361(c)(1), which helps multi-generational businesses. If your C Corp issued stock to 15 angel investors and three venture partners, you are still under the limit. But if you have 101 individual shareholders, you cannot convert until you consolidate.

Requirement 3: One Class of Stock

C Corps often issue preferred shares, voting shares, and non-voting shares. S Corps allow only one class of stock. Differences in voting rights alone do not create a second class, per Treas. Reg. 1.1361-1(l)(1). But if your C Corp issued preferred shares with a different dividend rate, those must be redeemed or converted before the election takes effect. This is where many business owners get tripped up and where professional guidance becomes critical.

Requirement 4: Eligible Shareholders Only

S Corp shareholders must be U.S. citizens or resident aliens, certain trusts (like grantor trusts and qualified Subchapter S trusts), or estates. Partnerships, corporations, and non-resident aliens cannot hold S Corp stock. If your C Corp has an LLC or another corporation as a shareholder, you must restructure ownership before filing Form 2553.

Requirement 5: No Ineligible Corporation Types

Certain corporations are permanently barred from S Corp status, including insurance companies, domestic international sales corporations (DISCs), and certain financial institutions. If your C Corp operates as a standard service business, consulting firm, tech company, or professional practice, this rule will not affect you.

For a comprehensive breakdown of how S Corp elections work across different business types, see our complete S Corp tax strategy guide for California.

The Built-In Gains Tax: The Hidden Conversion Cost Nobody Warns You About

Here is where the conversation gets uncomfortable. When your C Corp converts to an S Corp, the IRS does not simply forget about unrealized gains that existed on the date of conversion. Section 1374 of the Internal Revenue Code imposes a Built-In Gains (BIG) tax on any asset appreciation that occurred during your C Corp years, if those assets are sold within five years after the S Corp election takes effect.

How the BIG Tax Works in Practice

Suppose your C Corp purchased commercial equipment for $50,000 five years ago. On the day you convert to S Corp status, that equipment has a fair market value of $120,000. The built-in gain is $70,000. If you sell that equipment within the five-year recognition period, the S Corp pays a corporate-level tax on that $70,000 gain at the highest corporate rate of 21%, costing you $14,700 on top of your individual pass-through tax.

The BIG tax applies to inventory, real estate, equipment, accounts receivable (for accrual-basis taxpayers), and goodwill. The key strategy is to get a professional appraisal of all assets on the conversion date. This creates a documented baseline so the IRS cannot argue that post-conversion gains were actually built-in gains.

The Net Unrealized Built-In Gain Ceiling

The total BIG tax you pay in any single year is capped at your Net Unrealized Built-In Gain (NUBIG) as of the conversion date, reduced by any built-in gains recognized in prior years. If your NUBIG is zero or negative, you owe nothing. Many service-based C Corps with minimal tangible assets have little to no BIG tax exposure, making conversion nearly painless.

Pro Tip: Under the One Big Beautiful Bill Act (OBBBA), 100% bonus depreciation is now permanent. If you purchase new assets after conversion, you can immediately expense them, offsetting any income from built-in gain asset sales. Pair this with California’s $25,000 Section 179 cap under R&TC 17255 and maintain dual depreciation schedules to maximize both federal and state benefits.

KDA Case Study: Sacramento Medical Device Company Saves $41,200 After Year-Seven Conversion

Dr. Raj Patel founded a medical device distribution company in Sacramento as a C Corporation in 2019. His accountant at the time recommended the C Corp structure because Raj planned to take on investors. Those investors never materialized. For seven years, Raj operated as a solo owner paying double taxation on every dollar of profit.

When Raj came to KDA in late 2025, his company was generating $240,000 in annual net profit. His combined federal and California tax burden as a C Corp was $108,400 per year. KDA evaluated his eligibility for S Corp status and confirmed he met all five requirements under IRC 1361(b). His company had no preferred shares, one shareholder, and no ineligible ownership.

KDA filed Form 2553 by January 15, 2026, effective for the full 2026 tax year. We set Raj’s reasonable salary at $95,000, structured $145,000 as shareholder distributions, activated the AB 150 Pass-Through Entity (PTE) election to bypass the $40,000 SALT cap, established a Solo 401(k) with $23,500 in employee deferrals plus employer profit-sharing contributions, and prepared dual federal and California depreciation schedules for his existing equipment.

Result: Raj’s 2026 projected tax bill dropped to $67,200, a savings of $41,200 in year one. KDA’s engagement fee was $5,800, delivering a 7.1x first-year ROI. Over five years, the projected savings total $196,000, assuming stable revenue. The BIG tax exposure was minimal because Raj’s primary assets were inventory purchased at cost with negligible appreciation.

Ready to see how we can help you? Explore more success stories on our case studies page to discover proven strategies that have saved our clients thousands in taxes.

Step-by-Step: How to Convert Your C Corp to an S Corp in California

Converting a C Corp to an S Corp is not a single-form process. California adds its own layer of compliance on top of the federal requirements. Here is the complete eight-step conversion process, and if you want to see how the numbers look for your specific situation, run your profit through this small business tax calculator before you start.

Step 1: Evaluate BIG Tax Exposure

Before filing anything, get a professional appraisal of all corporate assets. Compare fair market value to tax basis. Document the Net Unrealized Built-In Gain. If the NUBIG is substantial, model whether the five-year BIG tax cost still makes conversion worthwhile. In most cases, it does.

Step 2: Eliminate Accumulated Earnings and Profits (AE&P)

C Corps carry Accumulated Earnings and Profits on their books. After S Corp election, distributions come first from the Accumulated Adjustments Account (AAA), then from AE&P. Distributions from AE&P are taxed as dividends under IRC 1368(c)(2). The smart move is to declare a dividend equal to your full AE&P balance before the S Corp election takes effect. This cleans the slate and prevents future dividend surprises.

Step 3: Restructure Stock if Necessary

If your C Corp has multiple classes of stock, redeem or convert all preferred shares into common shares before filing Form 2553. Record the restructuring in your corporate minutes. File any required securities amendments with the California Secretary of State.

Step 4: File IRS Form 2553

Submit Form 2553 to the IRS by March 15 of the tax year you want the election to begin. All shareholders must sign the form, consenting to the election. If you miss the March 15 deadline, you may qualify for late election relief under Rev. Proc. 2013-30, provided you file within three years and 75 days and meet reasonable cause requirements. See IRS Form 2553 instructions for the current version.

Step 5: File California Form 3560 (S Corporation Election or Termination)

California requires a separate entity formation filing. Submit FTB Form 3560 to confirm your state-level S Corp election. California does not automatically honor federal elections. Miss this step and the FTB will continue taxing your entity as a C Corp at the 8.84% rate instead of the 1.5% S Corp rate, a difference of $14,680 on $200,000 in net income.

Step 6: Set Up Payroll for Reasonable Salary

S Corp owners who work in the business must receive a W-2 salary that the IRS considers reasonable for the work performed. The landmark case Watson v. Commissioner established that the IRS will scrutinize artificially low salaries. Set your salary using BLS wage data for your occupation and geographic area. Register for California payroll tax accounts with the EDD.

Step 7: Activate the AB 150 PTE Election

California’s Pass-Through Entity Tax election under AB 150 allows S Corps to pay a 9.3% entity-level tax and receive a dollar-for-dollar credit on each shareholder’s individual return. This effectively bypasses the $40,000 SALT deduction cap imposed by OBBBA. The election must be made annually by the original filing deadline, and estimated payments begin June 15 of the election year.

Step 8: Establish Dual Depreciation Schedules

California does not conform to federal bonus depreciation under R&TC Sections 17250 and 24356. Your S Corp must maintain two separate depreciation schedules: one for federal (100% bonus depreciation) and one for California (standard MACRS without bonus). Failing to track this creates phantom income on your California return and potential FTB audit exposure.

Five Costliest Mistakes When Converting a C Corp to S Corp in Later Years

The conversion process has real traps. Here are the five mistakes that cost California business owners the most money.

Mistake 1: Ignoring the AE&P Balance ($8,000 to $35,000 Cost)

If you convert without eliminating AE&P, future distributions may be reclassified as taxable dividends. The IRS examines this during S Corp audits. A $100,000 distribution from AE&P triggers $23,800 in federal tax plus $13,300 in California tax. Clean out AE&P before the election date.

Mistake 2: Skipping the Asset Appraisal ($14,700+ Cost)

Without a documented appraisal on the conversion date, the IRS can argue that all gains recognized within five years are built-in gains subject to the 21% BIG tax under Section 1374. A $2,000 appraisal protects you from a $14,700 or higher tax surprise.

Mistake 3: Missing the California Form 3560 ($14,680+ Cost)

Filing Form 2553 with the IRS does not convert your California entity. You must separately file FTB Form 3560. Without it, California taxes your entity at the C Corp rate of 8.84% instead of the S Corp rate of 1.5%. On $200,000 profit, that oversight costs $14,680 in excess franchise tax alone.

Mistake 4: Setting an Unreasonable Salary ($24,000+ Cost)

Some owners convert to S Corp and then pay themselves a $30,000 salary on $250,000 in profit, hoping to minimize payroll taxes. The IRS reclassifies distributions as wages in these cases, per Watson v. Commissioner, and imposes back payroll taxes plus penalties. A $30,000 salary on $250,000 profit could trigger $24,000 in reclassification costs including the 20% accuracy-related penalty under IRC 6662.

Mistake 5: Forgetting the Five-Year Re-Election Lock ($50,000+ Cost)

Under IRC 1362(g), if your S Corp election is revoked or terminated, you cannot re-elect S Corp status for five full tax years without IRS consent via a Private Letter Ruling that costs approximately $15,300. Some owners accidentally trigger termination by issuing stock to an ineligible shareholder or creating a second class of stock through disproportionate loans. The five-year lockout at C Corp rates can cost $50,000 or more in excess taxes.

The OBBBA Changes That Make Converting Now More Valuable Than Ever

The One Big Beautiful Bill Act made several provisions permanent that dramatically increase the value of converting from C Corp to S Corp in 2026 and beyond.

Permanent QBI Deduction Under IRC Section 199A

The 20% Qualified Business Income deduction is now permanent. S Corp owners deduct 20% of their qualified business income before calculating federal tax. C Corp owners get zero QBI benefit. On $200,000 in S Corp pass-through income (after salary), the QBI deduction saves roughly $7,400 in federal tax annually. This deduction alone pays for most conversion costs within the first year.

100% Bonus Depreciation Made Permanent

OBBBA restored and made permanent 100% first-year bonus depreciation for qualified assets. S Corp owners who purchase equipment, vehicles over 6,000 pounds GVWR, or technology after conversion can immediately expense the full cost federally. A $75,000 equipment purchase generates $75,000 in first-year deductions. Remember, California does not conform, so maintain your dual schedules.

$40,000 SALT Cap (Up From $10,000)

The SALT deduction cap increased to $40,000 under OBBBA. While this helps, California S Corp owners using the AB 150 PTE election effectively bypass this cap entirely. The PTE tax paid at the entity level is not subject to the SALT limitation, making the S Corp structure even more valuable for high-income California owners.

$2.5 Million Section 179 Expensing

The Section 179 deduction limit jumped to $2.5 million federally under OBBBA. California maintains its own $25,000 cap under R&TC 17255, but the federal benefit is substantial for S Corps making large asset purchases.

Can You Convert Mid-Year or Do You Have to Wait?

Form 2553 filed by March 15 makes the election effective January 1 of that same year. If you file after March 15 but before the end of the tax year, the election becomes effective January 1 of the following year. There is no true “mid-year” conversion for a calendar-year C Corp converting to S Corp. The election is always effective at the start of a tax year.

However, if you recently missed the March 15 deadline, Rev. Proc. 2013-30 provides late election relief. You can file Form 2553 up to three years and 75 days after the intended effective date, provided you can demonstrate reasonable cause and have treated the entity as an S Corp on all filed returns. The IRS grants this relief routinely when the paperwork was simply overlooked.

What About the Split-Year Filing?

When a C Corp converts to S Corp effective January 1, the short C Corp year ends December 31 of the prior year. You file a final C Corp return (Form 1120) for that short year and begin filing Form 1120-S for the S Corp year. California requires the same split: a final Form 100 for the C Corp period and Form 100S for the S Corp period going forward. Both returns are due by the respective deadlines, and extension filings must be filed for each.

Three Narrow Scenarios Where Staying a C Corp Still Wins

Conversions are not universally right. Here are three situations where maintaining C Corp status makes strategic sense.

Scenario 1: Active Venture Capital Fundraising

Venture capital firms invest through LLCs and other entities that cannot hold S Corp stock. If you are actively raising a Series A or B round, converting to S Corp will disqualify your investors. Stay C Corp until funding is complete, then evaluate conversion.

Scenario 2: Qualified Small Business Stock (QSBS) Under Section 1202

C Corp shareholders who hold QSBS for five years can exclude up to $10 million in capital gains upon sale. This exclusion is only available to C Corp shareholders. If your C Corp qualifies and you plan to sell within 5 to 10 years, the QSBS benefit may exceed the annual S Corp tax savings. Run a five-year projection comparing both paths before deciding.

Scenario 3: Full Profit Retention for Rapid Growth

If your C Corp retains 100% of profits for expansion and never distributes dividends, the flat 21% federal rate may be preferable to the pass-through rate where owners owe tax on income they never received. But beware: the accumulated earnings tax under IRC Section 531 penalizes C Corps that retain profits beyond reasonable business needs, adding a 20% surtax on top of the corporate rate.

Frequently Asked Questions

Is There a Time Limit on When a C Corp Can Elect S Corp Status?

No. There is no statute of limitations on S Corp elections. A C Corp that has operated for 1 year or 30 years can file Form 2553 at any time, as long as it meets the eligibility requirements under IRC 1361(b). The only deadline is the March 15 annual cutoff for same-year effectiveness.

Do I Need Shareholder Approval to Convert?

Yes. Every shareholder must sign Form 2553 consenting to the S Corp election. If even one shareholder refuses, the election fails. For single-owner C Corps, this is a non-issue. For multi-shareholder entities, get signatures early to avoid deadline complications.

Will Converting Trigger an IRS Audit?

The conversion itself does not trigger an audit. However, the IRS Palantir SNAP AI system cross-references Form 2553 filings with prior C Corp returns. Discrepancies between reported income, AE&P balances, and shareholder distributions may generate automated notices. Clean records and proper documentation prevent issues.

What Happens to My C Corp’s Net Operating Losses?

Net Operating Losses (NOLs) generated during C Corp years do not carry forward to the S Corp. They remain suspended and can only offset income if the entity reverts to C Corp status. This is an important factor if your C Corp has significant unused NOLs.

Can I Convert Back to a C Corp if the S Election Does Not Work Out?

Yes, but with consequences. Under IRC 1362(d)(1), shareholders owning more than 50% of stock can revoke the election. However, IRC 1362(g) imposes a five-year waiting period before re-electing S Corp status. A Private Letter Ruling can waive this restriction, but costs approximately $15,300 and takes 6 to 12 months.

Does California Charge Extra Fees for the Conversion?

California does not charge a separate conversion fee. However, the S Corp pays a minimum $800 franchise tax under R&TC 17941, plus the 1.5% net income tax. If your entity previously paid the 8.84% C Corp franchise tax, your California tax bill drops significantly upon conversion. You must also account for the gross receipts fee under R&TC 17942 if your California gross receipts exceed $250,000.

This information is current as of April 16, 2026. Tax laws change frequently. Verify updates with the IRS or FTB if reading this later.

Book Your C Corp to S Corp Conversion Strategy Session

If your C Corporation has been bleeding unnecessary taxes for years and you have been wondering whether it is too late to switch, it is not. Every year you delay costs you $20,000 to $50,000 in avoidable double taxation. Book a personalized consultation with our strategy team and we will evaluate your BIG tax exposure, clean up your AE&P, file your Form 2553, and get your California compliance locked down from day one. Click here to book your consultation now.