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Official form guide
Form W4KO: W-4 (ko)
IRS Form W-4 (ko) is used by employees to tell their employer the correct amount of federal income tax to withhold from wages. It must be filed by employees (including nonresident alien employees) and a new form is required by 2027-02-16.
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IRS Form W4KO - W-4 (ko)
IRS Form W-4 (ko) is used by employees to tell their employer the correct amount of federal income tax to withhold from wages. It must be filed by employees (including nonresident alien employees) and a new form is required by 2027-02-16.
Risk Radar
Scan points- 1Submitting the form without the employee’s signature makes it invalid.
- 2Submitting the form without the employee’s signature, which invalidates the form.
- 3Failing to check the 2026 withholding exemption box when both exemption conditions are met.
- 4Entering an incorrect number of dependents or wrong dollar amounts on lines 3(a) or 3(b).
- 5Omitting the Social Security number when the form requires it.
Plain English
This form tells your employer how much federal tax to take out of each paycheck. You fill it out when you start a job or when your life changes, like getting married or having a child. The IRS checks the form for accuracy. If too little is taken out, you could owe tax and a penalty.
Submission Date
- Filing date: 2025-12-19 16:10:53
- Preparation window: collect IDs, supporting records, and signatures in advance.
- Final review: verify names, dates, and required fields before submission.
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What this form is for
- Use this form when an employee wants the employer to withhold the correct federal income tax from wages.
- Do not use it when you are a nonresident alien unless you have consulted Notice 1392 first.
- Check Form 1040 instead when you need to verify line 24 total tax on your 2025 return for exemption eligibility.
Form selector
Use this form or another form?
Need to confirm zero total tax in 2025 to claim withholding exemption
Exemption requires line 24 total tax to be zero
✓ Verify line 24 on your 2025 Form 1040 shows 0
Senior taxpayer filing 2025 return
Same exemption rule uses line 24 on Form 1040‑SR
✓ Confirm line 24 on your 2025 Form 1040‑SR is zero
You are filing a 2025 individual return and need to determine eligibility for withholding exemption
Total tax on line 24 determines exemption
✓ Verify line 24 on your 2025 Form 1040‑SR is zero
Deadline or filing window
When an employee’s personal or financial situation changes, a new W‑4 must be filed. The form must be submitted by 2027-02-16. No extension is provided in the source.
Checklist
What you need before filling it out
Name and address
Legal name and current mailing address · Step 1(a) personal information section
Social Security Number
SSN card · Step 1(b)
Filing status selection
Choice of single, married filing jointly, or head of household · Step 1(c)
Withholding exemption box
Checked box confirming both exemption conditions · Exemption section on page 2
Signature and date
Employee signature and date · Employee signature block on page 3
Before you submit
- 1Enter your full legal name exactly as shown on your SSN card
- 2Provide your current mailing address in the address field
- 3Enter your nine‑digit Social Security Number
- 4Select the correct filing status in step 1(c)
- 5If claiming exemption, check the exemption box and verify both 2025 conditions are satisfied
- 6Complete only steps 1(a), 1(b), and 5; leave all other steps blank
- 7Sign and date the form in the employee signature block
- 8Submit the completed form to your employer before 2027‑02‑16
- 9Retain a copy of the signed form for your records
How to file this form
- 1Fill in personal information (name, address, SSN) in step 1(a) and 1(b)
- 2Choose your filing status in step 1(c)
- 3If eligible for exemption, tick the exemption box on page 2
- 4Leave steps 2‑4 blank and complete step 5 only
- 5Sign and date the form in the employee signature section
- 6Give the signed form to your employer and keep a copy for yourself
Known limitations
- 1Form is invalid without the employee’s signature
- 2Exemption can be claimed only if both 2025 tax liability conditions are met
- 3Only one W‑4 should have steps 3‑4(b) completed when you have multiple jobs
- 4Nonresident alien employees must consult Notice 1392 before using this form
- 5If you have more than two jobs or a salary over $120,000, additional tables in Publication 505 may be required
Field map
Compact field-by-field guide
Personal Info
2 items
Your legal name and current mailing address.
Your taxpayer identification number — must match IRS records.
Filing Status
1 items
Single, Married Filing Jointly, or Head of Household (for withholding purposes).
Dependents
1 items
Number of qualifying children and other dependents.
Adjustments
1 items
Additional income not from jobs or adjustments to withholding.
Withholding
1 items
Additional amount you want withheld from each paycheck.
Certification
1 items
Your tax entity type: Individual, Corporation, Partnership, etc.
Signatures
1 items
Sign and date to certify under penalty of perjury.
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Fillable formOpen in Editor->Form W-4 (ko) is the 2026 edition, created on 12/19/25, and the latest information page is www.irs.gov/FormW4KO.
What changed or needs a fresh check
- Edition date — confirm the form shows (2026) and creation date 12/19/25
- Fee — Not stated in the official source
- Mailing address — Not stated in the official source
- Signature — confirm employee signature present as required
- Employer EIN — Not stated in the official source
Quick Facts
Downloads
After you file
- 1Keep the employer‑provided copy of the signed W‑4 for at least three years
- 2Check your first pay stub to verify the correct withholding amount
- 3If the withholding is incorrect, submit a new Form W‑4 to your employer
- 4Retain any correspondence about changes for future reference
- 5Monitor your 2026 tax liability to ensure exemption remains valid
- 6If you change jobs, complete a new Form W‑4 for the new employer
Sources
- SRCForm p.1 — revision shows (2026) and creation date 12/19/25
- SRCForm p.1 — purpose description states form enables employer to withhold correct federal income tax
- SRCForm p.2 — exemption conditions require 2025 tax liability zero as shown on line 24 of Form 1040 or 1040‑SR
- SRCForm p.2 — nonresident alien must consult Notice 1392 before completing the form
- SRCForm p.2 — new form must be submitted by 2027‑02‑16
- SRCForm p.3 — multiple‑job worksheet instructions for two or more jobs
- SRCForm p.1 — employee signature required for validity
- SRCForm p.2 — steps 1(a), 1(b), and 5 only; other steps not to be completed
- SRCForm p.2 — latest information page listed as www.irs.gov/FormW4KO
- SRCNot stated in the official source — verify on the agency site
Common confusion points
Do I need to fill out steps 2‑4 if I have only one job?
The instructions say only the highest‑paying job’s W‑4 includes steps 3‑4(b)
→ Ensure all other W‑4s are left blank for steps 2‑4
Can I claim exemption without checking the box?
Exemption requires both conditions and a checked box
→ Verify the box is checked only when conditions are met
What if my SSN does not match my card?
The form instructs to call SSA if names differ
→ Confirm SSN matches the card before signing
Should I use the estimator or the multiple‑job worksheet?
Both are options; one may be more accurate depending on job count and pay
→ Choose the method that matches your situation and enter the result
Is the deadline 2027‑02‑16 for all employees?
The source states new form must be submitted by that date
→ Check the submission date on the form and submit before it
Do I need to fill out 2(c) if I have concerns about non‑wage income?
Source allows selecting 2(b) instead if concerned about 2(c) information
→ Select step 2(b) when you prefer not to disclose 2(c) details
Workflow map
Related forms and next steps
Before
Current
⚠ If something goes wrong
- Form 1040 – file an amended return to correct tax liability affecting exemption
Questions about IRS Form W4KO
What is IRS Form W4KO used for?
This form tells your employer how much federal tax to take out of each paycheck. You fill it out when you start a job or when your life changes, like getting married or having a child. The IRS checks the form for accuracy. If too little is taken out, you could owe tax and a penalty.
Who must file IRS Form W4KO?
Employees, including nonresident alien employees, must complete IRS Form W‑4 (ko).
What information does IRS Form W4KO require?
The form gathers personal data (name, address, SSN, filing status), multiple‑job information, dependent credits (lines 3(a)–3(b)), other income and deductions (lines 4(a)–4(b)), any extra withholding (line 4(c)), and the employee’s signature.
When is IRS Form W4KO due?
A new Form W‑4 (ko) must be submitted by 2027-02-16.
How do I complete IRS Form W4KO?
First, complete step 1(a) with name and address, then step 1(b) with Social Security number and filing status. Skip all other numbered steps unless you need them, and finish by signing in step 5. Provide the completed form to your employer for payroll processing.
What happens if IRS Form W4KO is filed incorrectly?
If too little tax is withheld, the employee may owe tax and can be assessed a penalty (가산세).
Do I need to fill out steps 2‑4 if I have only one job?
The instructions say only the highest‑paying job’s W‑4 includes steps 3‑4(b) Ensure all other W‑4s are left blank for steps 2‑4
Can I claim exemption without checking the box?
Exemption requires both conditions and a checked box Verify the box is checked only when conditions are met
Source transparency
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