California Form 100-ES is the Corporation Estimated Tax voucher that every corporation doing business in California uses to pay its income or franchise tax in four installments during the taxable year. You file it with the California Franchise Tax Board whenever your expected tax — including the $800 minimum franchise tax — will be $500 or more.
Miss a single installment, underpay by even a few dollars, or use the wrong installment percentage, and the FTB will assess an underpayment penalty under Revenue and Taxation Code §19142 that compounds quietly until you file your annual Form 100. According to the FTB’s most recent Annual Report, more than 1.6 million California corporate returns are filed each year, and estimated tax underpayment is among the top five corporate penalty categories the agency issues.
Here is what you will learn in this guide:
- 📋 How to complete every box on Form 100-ES line by line with sample entries
- 🧮 How to calculate each installment using the 30%, 40%, 0%, 30% schedule
- 🏢 Three full walkthroughs for a first-year corporation, a profitable established C-corp, and a large corporation over $1 million in income
- 💻 How to pay through Web Pay, EFT, credit card, or paper voucher
- ⚠️ The most common Form 100-ES mistakes and the exact penalty each one triggers
What Form 100-ES Is and Who Must File It
California Form 100-ES is the Corporation Estimated Tax voucher that corporations use to prepay their California income or franchise tax during the year the income is earned. It is authorized by R&TC §19023, which defines the term “estimated tax” as the amount of tax the corporation expects to owe for the taxable year. The voucher itself does not report income; it simply transmits the payment and ties it to the correct entity and tax year.
Every corporation subject to the California franchise or income tax must file Form 100-ES if the total expected tax for the year is $500 or more, per the official FTB instructions. This includes C corporations filing Form 100, S corporations filing Form 100S (which pay a 1.5% entity-level tax plus the $800 minimum), banks and financial corporations, exempt organizations with unrelated business taxable income filing Form 109, and corporations subject to the alternative minimum tax. A newly incorporated or qualified corporation is not required to make an estimated payment for the $800 minimum tax in its first taxable year under R&TC §23153, but it must still pay estimated tax on actual measured income above that floor.
The form interacts with several other filings. It feeds payments into the annual Form 100 or Form 100S, it pairs with Form 100-WE (water’s-edge election) when applicable, and it is reconciled at year-end on Form 5806, the Underpayment of Estimated Tax by Corporations form. Ignoring Form 100-ES while filing Form 100 on time does not erase the underpayment penalty — the two penalties operate independently.
Before You Start: Documents and Information You Need
Gathering the right information before you open the voucher prevents the two most expensive errors on Form 100-ES — paying under the wrong entity identifier and miscalculating the installment amount. The FTB matches payments using your California corporation number, your Secretary of State (SOS) file number, and your FEIN in that order of priority, so all three must be on hand. The agency’s MyFTB business portal can confirm the corporation number if you do not have your incorporation paperwork nearby.
Use this pre-filing checklist before completing any voucher:
- Prior-year Form 100 or 100S — needed to compute the prior-year safe harbor under R&TC §19025; without it, you cannot use the safer of the two calculation methods.
- Current-year income projection — required for the annualized income method and to detect a large-corporation override; missing this forces you to overpay or underpay.
- California corporation number (7 digits) — the FTB’s primary key for posting payments; a wrong number routes your payment to another entity and triggers a “failure to pay” notice.
- Secretary of State file number (12 digits for LLCs converted to corps) — secondary identifier used when the corporation number is unknown; missing it slows posting by weeks.
- Federal Employer Identification Number (FEIN) — used for federal cross-matching; a missing FEIN can trigger an IRS information-sharing flag.
- Taxable year beginning and ending dates — critical for fiscal-year filers; a wrong year on the voucher posts the payment to the wrong period.
- Apportionment data for multistate filers — California sales, payroll, and property factors needed under the single-sales-factor formula in R&TC §25128.7; missing this forces a default to 100% California sourcing.
- Bank routing and account numbers — required if you plan to pay through Web Pay or are an EFT-mandatory filer under R&TC §19011.
- Prior-year overpayment amount applied forward — reduces the first installment dollar-for-dollar and must be confirmed on last year’s Form 100, line 41.
- Estimated AMT and credits — alternative minimum tax under R&TC §23455 and nonrefundable credits adjust the installment base.
Each of these items has a direct consequence if missing. For example, omitting the prior-year overpayment causes you to double-pay the first installment, and missing the apportionment data can swing your tax liability by tens of thousands of dollars for multistate corporations.
Where to Get the Form and How to Access It
The official, current Form 100-ES is published on the FTB website each tax year and can be downloaded as a fillable PDF from the 2025 Form 100-ES page. The form is revised annually — the revision date appears in the lower-left corner of the voucher (e.g., “FTB 100-ES 2025”) — and using an outdated year on a voucher will cause the payment to post to the wrong taxable period.
You can also access the form three other ways. First, the FTB Forms and Publications search lets you pull historical versions for amended returns or late-filed prior-year payments. Second, tax software such as Lacerte, ProSeries, Drake, and CCH Axcess automatically populates Form 100-ES from the prior-year Form 100 inside the corporate module. Third, you can request paper vouchers by calling the FTB at 800-852-5711, though paper delivery typically takes 7 to 10 business days and is not recommended for first-installment filers near the April 15 deadline.
Do not download Form 100-ES from third-party sites or generic tax blogs. The FTB rejects vouchers that have altered scan lines, OCR boxes, or barcodes, and a rejected voucher counts as no payment received for penalty purposes. If you must print a paper voucher, use a laser printer on plain white paper, do not staple, and do not write outside the boxes.
Step-by-Step: How to Fill Out Form 100-ES Line by Line
Form 100-ES is a single-page voucher with four detachable installment slips, each containing the same set of fields. You complete one voucher per installment, and the FTB scans the OCR line at the bottom to post the payment. The fields below appear on every voucher in the order printed on the official 2025 form.
Taxable Year (TYB and TYE)
The Taxable Year field asks you to enter the beginning and ending dates of your corporation’s taxable year. Calendar-year filers enter 01/01/2026 and 12/31/2026; fiscal-year filers enter the actual start and end dates in MM/DD/YYYY format with no dashes or slashes other than those printed.
A specific example: Pacific Ridge Coffee Inc., a calendar-year C-corp, enters TYB 01/01/2026 and TYE 12/31/2026 on its first 2026 installment voucher. Fiscal-year filer Harbor Steel Co. with a July–June year enters TYB 07/01/2026 and TYE 06/30/2027.
The most common edge case is a short-period return after a merger or change of accounting period. In that situation, enter the actual short-period beginning and ending dates exactly as they will appear on the eventual Form 100. The most common mistake is leaving these dates blank because the printed voucher already lists “2026” in the header — the FTB still requires the exact MM/DD/YYYY range, and a blank year field causes the payment to post to the current calendar year by default, which can trigger a misapplied-payment notice. The misconception filers hold is that calendar-year filers can skip the dates; they cannot.
California Corporation Number
This field asks for the 7-digit California corporation number assigned by the Secretary of State at incorporation or qualification. Enter the number left-justified with no leading “C” prefix and no spaces; the FTB uses this as the primary key to post payments.
For example, Pacific Ridge Coffee Inc. enters its number as 1234567. If you do not know the number, look it up free of charge on the California Secretary of State Business Search.
The nuance arises for LLCs that converted to corporations — they may have a 12-digit SOS file number instead of a 7-digit corporation number. In that case, leave the corporation-number box blank and write the 12-digit number in the SOS file number box below. The most common mistake is entering the FEIN here by accident, which posts the payment to a nonexistent corporation account and triggers an immediate “no payment received” notice on your Form 100. The misconception is that the corporation number and the SOS file number are the same; they are not, and using one in the other’s box guarantees a posting error.
Secretary of State (SOS) File Number
The SOS file number is the 12-digit identifier assigned to LLCs, limited partnerships, and out-of-state entities that registered with the California Secretary of State. Enter the number only if your entity does not have a 7-digit corporation number; otherwise leave it blank.
A specific example: Bayview Holdings LLC, an LLC taxed as a C-corp under a federal Form 8832 election, enters 201912345678 in this field and leaves the corporation-number box empty.
The edge case is dual-registered entities — a Delaware corporation that also qualified in California will have both a corporation number and an SOS file number. In that case, use the corporation number only, per the FTB instructions for Form 100-ES. The common mistake is entering both numbers, which causes the OCR scanner to fail and routes the voucher for manual processing — adding three to six weeks of posting delay. The misconception is that the SOS file number is optional decoration; for non-corporate entities taxed as corporations, it is the only identifier the FTB has.
Federal Employer Identification Number (FEIN)
This field asks for the 9-digit FEIN issued by the IRS, entered in the format XX-XXXXXXX. The FTB uses the FEIN to cross-match payments against IRS records and to verify the entity for combined-report members.
For example, Pacific Ridge Coffee Inc. enters 87-1234567. If your corporation has not yet received its FEIN, do not file Form 100-ES until you have one; apply through the IRS EIN application portal first.
The nuance for combined-report filers is that the key corporation’s FEIN goes on the voucher, not the FEIN of a subsidiary, even if the subsidiary writes the check. The most common mistake is reversing two digits — a one-digit FEIN typo causes the FTB to issue a mismatch notice and can delay posting by 30 days. The misconception is that the FEIN replaces the California corporation number; it does not, and a voucher with only the FEIN may be rejected outright.
Corporation Name
Enter the exact legal name of the corporation as registered with the California Secretary of State. Use all capital letters, no abbreviations unless they appear in the registered name, and include suffixes like “INC.”, “CORP.”, or “LLC” exactly as filed.
A specific example: Pacific Ridge Coffee Inc. enters PACIFIC RIDGE COFFEE INC. in the name box. Harbor Steel Co. enters HARBOR STEEL CO.
The edge case is a corporation that has filed a Certificate of Amendment to change its name mid-year. Use the new name once the amendment is effective, and attach a brief note to the voucher referencing the prior name. The most common mistake is using a DBA or trade name instead of the legal name, which causes the FTB to flag the payment for identity review. The misconception is that the name does not matter because the corporation number is the key — it matters, because the FTB cross-checks both, and a mismatch creates a manual-review hold.
Address (Street, City, State, ZIP)
The address fields ask for the corporation’s current mailing address on file with the FTB. Enter the street number and name on one line, suite or unit on a separate sub-line, then city, two-letter state code, and 5- or 9-digit ZIP code.
For example, Pacific Ridge Coffee Inc. enters 1450 MARKET ST, SUITE 200, SAN FRANCISCO, CA 94103. A P.O. Box is acceptable for mailing but not for the principal office address required on Form 100.
The nuance is foreign addresses for out-of-state corporations qualified in California — enter the foreign address exactly as it appears with country code spelled out. The common mistake is using the registered agent’s address instead of the corporation’s own mailing address, which sends FTB notices to the agent and can cause missed deadline notices. The misconception is that the address on Form 100-ES updates your address on file with the FTB; it does not — file Form 3533-B, the Change of Address for Businesses, to update the official record.
Installment Number (1, 2, 3, or 4)
The installment number identifies which of the four estimated payments this voucher represents. Mark the appropriate box (1, 2, 3, or 4) corresponding to the installment due dates set by R&TC §19025.
For a calendar-year filer, Pacific Ridge Coffee Inc. marks Installment 1 on its April 15, 2026 voucher, Installment 2 on June 15, Installment 3 on September 15, and Installment 4 on December 15. Fiscal-year filers use the 15th day of the 4th, 6th, 9th, and 12th months of their fiscal year.
The edge case is a short-period filer whose taxable year ends before the fourth installment due date — they file only the installments due during the short period. The common mistake is leaving the installment box unmarked, which causes the FTB scanner to default to installment 1 and creates phantom underpayments for later installments. The misconception is that you can combine two installments on one voucher; you cannot — each installment requires its own voucher with its own check or electronic confirmation number.
Amount of Payment
The amount of payment field asks for the dollar amount of this installment, entered in whole dollars with no commas, no dollar sign, and no cents (round to the nearest dollar). The installment must equal the percentage of the year’s estimated tax shown on the Estimated Tax Worksheet in the Form 100-ES instructions.
For example, Pacific Ridge Coffee Inc. estimates $40,000 of total 2026 tax. Its four installments are $12,000 (30%), $16,000 (40%), $0 (0%), and $12,000 (30%). Enter each amount in the corresponding voucher.
The installment percentages under California law are 30%, 40%, 0%, and 30% — not the equal 25% used at the federal level. This is the single most-missed nuance on the form. The common mistake is paying 25% each quarter on the federal pattern, which underpays installments 1 and 2 by 5% and 15% respectively, triggering an R&TC §19142 penalty even if the total annual payment is correct. The misconception is that the third-quarter $0 installment is a typo on the form; it is not — California intentionally back-loads the schedule, and writing a “make-up” payment on installment 3 does not protect against a later shortfall on installment 4.
Estimated Tax Worksheet (Kept With Records)
The Estimated Tax Worksheet is not submitted with the voucher but must be retained in the corporation’s records. It calculates expected tax by starting with projected net income, applying the 8.84% C-corp rate (or 10.84% for banks and financials, or 1.5% S-corp rate plus the $800 minimum), subtracting credits, and adding AMT under R&TC §23455.
A specific example: Harbor Steel Co. projects $1,200,000 of net California income. Multiplying by 8.84% yields $106,080 of regular tax; with no credits and no AMT, the total estimated tax is $106,080, and the four installments are $31,824, $42,432, $0, and $31,824.
The nuance is the large-corporation rule under R&TC §19025(b) — corporations with $1 million or more of California net income in any of the three prior years must base installments 2, 3, and 4 on the current year’s tax, not the prior-year safe harbor. The common mistake is using prior-year safe harbor when ineligible, which retroactively converts every installment into an underpayment. The misconception is that the worksheet is optional paperwork; FTB auditors request it during examinations, and without it the safe-harbor defense fails.
Three Filled-Out Examples Using Real Scenarios
These three scenarios walk through Form 100-ES start to finish for the most common filer profiles. Each table shows what the named filer writes in each major field of the first installment voucher.
Scenario 1: First-Year Corporation Owing Only the Minimum Tax
Coastal Bloom Florals Inc. incorporated in California on February 1, 2026, and projects $40,000 of net income in its first year. Under R&TC §23153, it owes no $800 minimum tax in its first year, but it still owes 8.84% of $40,000 = $3,536 in estimated tax.
| Form Section | What Coastal Bloom Florals Inc. Enters |
|---|---|
| Taxable Year (TYB / TYE) | 02/01/2026 / 12/31/2026 |
| California Corporation Number | 4567890 |
| SOS File Number | (blank) |
| FEIN | 92-7654321 |
| Corporation Name | COASTAL BLOOM FLORALS INC. |
| Address | 88 OCEAN AVE, SANTA MONICA, CA 90401 |
| Installment Number | 1 |
| Amount of Payment | $1,061 (30% of $3,536) |
Scenario 2: Established Profitable C-Corp Using Prior-Year Safe Harbor
Pacific Ridge Coffee Inc., a calendar-year C-corp, owed $36,000 in California tax for 2025 and projects $42,000 for 2026. Because it is not a large corporation, it uses the lesser of 100% of prior-year tax or 100% of current-year tax — here, the $36,000 safe harbor.
| Form Section | What Pacific Ridge Coffee Inc. Enters |
|---|---|
| Taxable Year (TYB / TYE) | 01/01/2026 / 12/31/2026 |
| California Corporation Number | 1234567 |
| SOS File Number | (blank) |
| FEIN | 87-1234567 |
| Corporation Name | PACIFIC RIDGE COFFEE INC. |
| Address | 1450 MARKET ST, SUITE 200, SAN FRANCISCO, CA 94103 |
| Installment Number | 1 |
| Amount of Payment | $10,800 (30% of $36,000) |
| Payment Method | Web Pay ACH debit |
Scenario 3: Large Corporation Over $1 Million in Income
Harbor Steel Co. had $1,400,000 of California net income in 2025 and projects $1,500,000 for 2026. As a “large corporation” under R&TC §19025(b), it may use prior-year tax only for installment 1; installments 2, 3, and 4 must be based on current-year projected tax of $132,600 (8.84% of $1,500,000).
| Form Section | What Harbor Steel Co. Enters |
|---|---|
| Taxable Year (TYB / TYE) | 01/01/2026 / 12/31/2026 |
| California Corporation Number | 7654321 |
| SOS File Number | (blank) |
| FEIN | 45-9876543 |
| Corporation Name | HARBOR STEEL CO. |
| Address | 2200 INDUSTRIAL BLVD, FONTANA, CA 92335 |
| Installment Number | 1 |
| Amount of Payment | $37,128 (30% of prior-year $123,760) |
| Subsequent Installments | Recomputed to current-year base |
How to File the Completed Form 100-ES
Form 100-ES can be paid through four channels, but corporations with a single payment of $20,000 or more, or a total prior-year tax liability over $80,000, are mandatory EFT filers under R&TC §19011 and must pay electronically or face a 10% noncompliance penalty.
The FTB Web Pay portal is the FTB’s preferred channel — there is no fee, the payment posts within one to two business days, and you receive an electronic confirmation number that serves as proof of filing. Schedule the payment by 3:00 p.m. Pacific the day before the due date to guarantee timely posting.
The EFT credit or debit option through the FTB’s EFT program is required for mandatory filers. Initiate the transaction through your bank’s ACH service, use the FTB’s tax-type code 02100 for corporation estimated tax, and keep the bank trace number as your proof of payment.
Credit card payments are accepted through ACI Payments, Inc. at 800-2PAY-TAX, with a third-party convenience fee of approximately 2.3% of the payment. Processing time is one business day, and the ACI confirmation number is your proof of filing.
Paper voucher by mail is the slowest channel. Make the check payable to Franchise Tax Board, write the corporation number, FEIN, and “2026 Form 100-ES” on the check, and mail to:
Franchise Tax Board, P.O. Box 942857, Sacramento, CA 94257-0531
Allow 7 to 10 business days for posting. Keep the certified-mail receipt as proof of timely filing under the timely-mailing-is-timely-filing rule of R&TC §21027.
What Happens After You File
Once the FTB receives your Form 100-ES payment, it posts to your corporation’s account, viewable in MyFTB within 2–10 business days depending on channel. The payment is held in suspense until you file the annual Form 100, at which point all four installments are reconciled against the total tax liability.
If you underpaid any installment, the FTB computes a penalty under R&TC §19142 using the federal short-term rate plus 3%, compounded daily from the installment due date until the earlier of the next installment date or the original return due date. The penalty appears on your annual Form 100 as part of the total balance due, and you reconcile it on Form 5806.
If you overpaid, the excess is not refunded automatically. You must either request a refund on Form 100 line 41 or check the box to apply the overpayment to next year’s first installment. The misconception that overpayments roll forward without action causes many corporations to lose the time value of money for an entire year.
Mistakes to Avoid When Filling Out the Form
Here are the ten most common Form 100-ES errors and the consequence of each:
- Using the federal 25% installment pattern instead of the California 30/40/0/30 split — triggers an underpayment penalty on installments 1 and 2 under R&TC §19142.
- Entering the FEIN in the corporation number box — routes the payment to a nonexistent account and generates a “no payment received” notice.
- Forgetting that large corporations cannot use prior-year safe harbor for installments 2–4 — converts an entire year of estimates into underpayments.
- Paying with a personal check from an officer’s account — the FTB may apply the payment to the officer’s personal tax account instead of the corporation’s.
- Mailing without a voucher — the check posts to an unidentified-payments queue and can take 60+ days to locate.
- Using an outdated form year (e.g., 2024 voucher for a 2026 payment) — posts the payment to the wrong tax year.
- Skipping installment 3 because it shows 0% — fine for most filers, but a large corporation using the annualized-income method may owe a nonzero installment 3.
- Missing the EFT mandate threshold of $80,000 prior-year liability — triggers an automatic 10% EFT noncompliance penalty under R&TC §19011.
- Forgetting to apply prior-year overpayment — causes a double payment of installment 1 and ties up cash flow.
- Writing the wrong tax year on the check memo — even with a correct voucher, an inconsistent check can route the payment to a prior period and create phantom underpayments.
Do’s and Don’ts
These do’s and don’ts come straight from the FTB’s corporation tax booklet and 30 years of practitioner experience.
- Do use Web Pay whenever possible because it gives you an instant confirmation number that serves as ironclad proof of timely payment.
- Do keep the Estimated Tax Worksheet in your records for at least four years because the FTB can examine estimated payments during a Form 100 audit.
- Do mark the installment number clearly because a blank installment box defaults to installment 1 and creates phantom shortfalls.
- Do reconcile installments on Form 5806 at year-end to confirm no penalty is owed.
- Do update the FTB address with Form 3533-B because notices sent to an outdated address still count as legally delivered.
- Do use the exact corporation number from the Secretary of State because it is the FTB’s primary posting key.
- Don’t pay through Web Pay after 3:00 p.m. Pacific on the due date because the transaction may post the next business day and miss the deadline.
- Don’t combine two installments on one voucher because the FTB’s scanner cannot split the payment automatically.
- Don’t rely on prior-year safe harbor if you are a large corporation because the rule does not apply to installments 2–4.
- Don’t write personal information like a Social Security number on the voucher because it creates an identity-cross-reference error.
- Don’t staple, paper-clip, or fold the voucher because it disrupts the OCR scanner.
- Don’t use Form 100-ES to pay a balance due from Form 100 because the correct voucher for that is Form 3539, the automatic extension payment voucher.
Pros and Cons of Filing on Your Own vs. With a Tax Professional
Most small corporations can file Form 100-ES on their own through Web Pay, but mid-size and large corporations almost always benefit from professional help because of the apportionment, large-corporation, and AMT calculations involved.
Pros of filing yourself:
- Saves the $300–$1,500 annual fee a CPA charges for quarterly estimate calculations.
- Builds in-house familiarity with the FTB Web Pay system and MyFTB portal.
- Lets you adjust installments mid-year as actual income comes in.
- Avoids preparer-error risk because you control every input directly.
- Gives you direct access to FTB notices through MyFTB rather than waiting for a CPA to forward them.
Cons of filing yourself:
- Easy to miss the 30/40/0/30 California schedule and default to federal 25% quarters.
- No second set of eyes on apportionment factors, which swing tax liability significantly for multistate corporations.
- You bear full responsibility for detecting the large-corporation override under R&TC §19025(b).
- AMT and credit calculations are easy to miscalculate without tax software.
- Penalty exposure under R&TC §19142 compounds quietly until you file Form 100.
Form 100-ES vs. Form 3539 at a Glance
These two vouchers are frequently confused because both are paid to the FTB and both involve a corporation’s annual tax cycle, but they serve very different purposes.
| Feature | Form 100-ES vs. Form 3539 |
|---|---|
| Purpose | 100-ES pays estimated tax during the year; 3539 pays a balance due at extension |
| Number of payments | 100-ES = four installments; 3539 = one payment |
| Due dates | 100-ES = 4th, 6th, 9th, 12th month 15th; 3539 = original return due date |
| Penalty if missed | 100-ES triggers underpayment penalty; 3539 triggers late-payment penalty |
| Applies to | 100-ES = corporations with expected tax ≥ $500; 3539 = corporations needing extra time to file |
FAQs
Who must file California Form 100-ES?
Yes — every corporation subject to California franchise or income tax must file Form 100-ES if its expected annual tax, including the $800 minimum, is $500 or more under R&TC §19023.
Does a first-year corporation owe the $800 minimum estimated tax?
No — newly incorporated or qualified corporations are exempt from the $800 minimum tax in their first taxable year under R&TC §23153, though they still owe estimated tax on measured income.
What are the four installment due dates?
Yes — for calendar-year filers, installments are due April 15, June 15, September 15, and December 15; fiscal-year filers use the 15th day of the 4th, 6th, 9th, and 12th months.
What percentage of estimated tax is due each installment?
Yes — California requires 30%, 40%, 0%, and 30%, not the federal 25% each quarter, under R&TC §19025.
Do I write the FEIN or the California corporation number in the corp-number box?
No — that box is for the 7-digit California corporation number only; the FEIN goes in a separate field, and swapping them causes posting errors.
What if I do not have a California corporation number yet?
No — do not file Form 100-ES until the Secretary of State has assigned your corporation number, because the voucher cannot post without it.
Can I leave the SOS file number blank?
Yes — leave it blank if you have a 7-digit corporation number; the SOS file number is used only by LLCs and entities without a corporation number.
What is the large-corporation rule?
Yes — corporations with $1 million or more of California net income in any of the past three years cannot use prior-year safe harbor for installments 2–4 under R&TC §19025(b).
Must I pay electronically?
Yes — corporations with any single payment of $20,000 or more, or prior-year liability over $80,000, must pay by EFT under R&TC §19011 or face a 10% penalty.
What happens if I underpay an installment?
Yes — the FTB assesses an underpayment penalty computed on Form 5806 under R&TC §19142 at the federal short-term rate plus 3%.
Can I apply last year’s overpayment to this year’s first installment?
Yes — check the apply-forward box on prior-year Form 100 line 41, and the overpayment reduces installment 1 dollar-for-dollar.
Does Form 100-ES update my address with the FTB?
No — file Form 3533-B to change the corporation’s address of record; the address on Form 100-ES does not update FTB systems.
Can I combine two installments on a single voucher?
No — each installment requires its own voucher and its own payment, because the FTB scanner cannot split a single voucher across two periods.
What if my installment 3 is $0 — do I still file a voucher?
No — if the calculation is truly $0, you do not file a voucher for installment 3, but you must still complete Form 5806 at year-end to confirm no penalty is owed.
Related reading
- How to Fill Out California Form NC-210 (w/Examples) + FAQs
- How to Fill Out California Form 540-ES (w/Examples) + FAQs
- How to Fill Out California Form 100 (w/Examples) + FAQs
- How to Fill Out California Form 100-W (w/Examples) + FAQs
- How to Fill Out California Form 100S (w/Examples) + FAQs
- How to Fill Out California Form FTB 3539 (w/Examples) + FAQs