Section 125 Health Insurance: How Your Premium Comes Out Pre-Tax
Section 125 health insurance is not a type of insurance. It is the employer cafeteria plan that lets you pay your health premium with pay that has not been taxed for Social Security, Medicare or federal income tax. This guide shows a worked savings example using KFF average premiums, where the deduction appears on your pay stub and W-2, which events let you change an election mid-year, and an email to send HR.
- Employee-paid accident and health premiums through a cafeteria plan are exempt from income tax withholding, Social Security tax and Medicare tax (IRS Publication 15-B, 2026).
- The employee share of FICA is 7.65%, made up of 6.2% Social Security and 1.45% Medicare, and the Social Security wage base is $184,500 in 2026 (IRS Publication 15, 2026).
- Workers paid an average of $1,440 a year for single coverage and $6,850 for family coverage in 2025, out of premiums of $9,325 and $26,993 (KFF, 2025 Employer Health Benefits Survey).
- A Section 125 election generally stays in place for the plan year, and changes are limited to events listed in 26 CFR 1.125-4, such as marriage, divorce, birth or adoption (IRS, 2026).
- Employers must report the cost of employer-sponsored health coverage in W-2 Box 12 with code DD (IRS General Instructions for Forms W-2 and W-3, 2026).
If your pay stub shows a Section 125 line next to your health insurance, the short answer is that your premium is being paid with pay that has not been taxed yet. Section 125 is the tax rule, and your health plan is the coverage. This guide shows what you save, where the deduction appears, and what to ask HR if something looks wrong.
Reviewed by a licensed benefits professional. Last reviewed: October 15, 2026.
What is Section 125 health insurance?
Section 125 health insurance is health coverage you pay for through your employer's Section 125 cafeteria plan, so the premium comes out of your pay before most taxes. The insurance itself comes from a carrier. Section 125 only changes how the premium is taxed.
A Section 125 plan, also called a cafeteria plan, is a written employer plan that lets employees choose between cash pay and certain benefits. A cafeteria plan can include accident and health benefits (IRS Publication 15-B, 2026). When the plan is set up correctly, employee-paid accident and health premiums are exempt from income tax withholding, Social Security tax and Medicare tax (IRS Publication 15-B, 2026).
| Item | What it is | Who provides it |
|---|---|---|
| Health plan | The coverage: doctors, deductible, claims | Insurance carrier chosen by your employer |
| Section 125 plan | The tax rule that lets you pay the premium pre-tax | Your employer, through a written plan document |
| Pay stub line | Shows the pre-tax premium, often labeled caf125, sec 125 or h125 | Your payroll provider |
Benecor's Section 125 pre-tax guide covers the federal rules in more detail, and the guide to what employees get from a cafeteria plan lists the other benefits that can run through the same plan.
How much does Section 125 health insurance save you?
Section 125 health insurance saves the typical employee about 19.65 cents on every pre-tax premium dollar, which is 12% federal income tax plus 7.65% FICA. State income tax, if your state has one, can add more.
Here is a worked example using the 2025 average worker contributions from KFF. The numbers are hypothetical for your situation. The example assumes a 12% federal income tax bracket for illustration. The 7.65% FICA rate is 6.2% Social Security plus 1.45% Medicare (IRS Publication 15, 2026).
| Coverage | Your yearly share (KFF 2025) | Your monthly share | FICA saved at 7.65% | Federal income tax saved at 12% | Total saved per year |
|---|---|---|---|---|---|
| Single | $1,440 | $120.00 | $110.16 | $172.80 | $282.96 |
| Family | $6,850 | $570.83 | $524.03 | $822.00 | $1,346.03 |
Your real savings depend on your bracket. If you earn above the Social Security wage base of $184,500 in 2026, the 6.2% part stops applying to your pay above that line (IRS Publication 15, 2026). The same plan also runs your health FSA, which is capped at $3,400 for plan years beginning in 2026 (IRS Publication 15-B, 2026).
Where does Section 125 health insurance show up on my pay stub and W-2?
Section 125 health insurance shows up as a pre-tax deduction on your pay stub and as a lower amount in W-2 Box 1 than your gross pay. Labels vary by payroll system, so the wording may not say health.
| Document | What to look for | Source |
|---|---|---|
| Pay stub | A pre-tax deduction labeled caf125, sec 125, h125 or medical | Your payroll provider |
| W-2 Box 1 | Wages should be lower than gross pay by your pre-tax deductions | IRS Publication 15-B, 2026 |
| W-2 Box 12, code DD | Cost of employer-sponsored health coverage | IRS General Instructions for Forms W-2 and W-3, 2026 |
| W-2 Box 14 | Some employers print a Section 125 amount here, with a label of their choice | Employer choice |
If the numbers do not match, ask payroll to explain the difference. Benecor's guides to Box 12 code DD and W-2 Box 14 for Section 125 explain each line, and the pay stub label guide decodes the common abbreviations.
Can I change my Section 125 health insurance election mid-year?
Usually only after a qualifying life event, and only if your plan allows it. Under 26 CFR 1.125-4, a cafeteria plan may let you change an election during the plan year only for the reasons the rule lists, and the plan is not required to allow any of them.
The change must also fit the event. If you gain a dependent, you can add coverage, but you generally cannot use that event to cancel coverage for someone else (26 CFR 1.125-4, 2026).
| Event | Example | Source |
|---|---|---|
| Marital status | Marriage, divorce, legal separation, death of a spouse | 26 CFR 1.125-4(c)(2) |
| Number of dependents | Birth, adoption, placement for adoption, death of a dependent | 26 CFR 1.125-4(c)(2) |
| Employment status | Starting or ending a job, unpaid leave, a strike or lockout | 26 CFR 1.125-4(c)(2) |
| Dependent eligibility | A child aging off the plan or losing eligibility | 26 CFR 1.125-4(c)(2) |
| Residence | A move that changes which plans you can use | 26 CFR 1.125-4(c)(2) |
| Other permitted changes | HIPAA special enrollment, court orders, Medicare or Medicaid entitlement, significant cost or coverage changes, FMLA leave | 26 CFR 1.125-4(b), (d) to (g) |
Benecor's list of Section 125 qualifying life events walks through the timing rules. Plans set their own deadline for asking, so check your plan document before the window closes.
What makes a Section 125 health deduction valid?
A Section 125 health deduction is valid when your employer has a written cafeteria plan and you made an election under it. Without a written plan, pre-tax treatment can be lost and the premium counts as taxable pay (Proposed Treasury Regulation Section 1.125-1(c)).
| Piece | What to ask for |
|---|---|
| Written plan document | A copy of the Section 125 plan, or the page that lists your health benefit |
| Your election | The signed or electronic form showing the premium amount you chose |
| Plan year | The dates your election covers and the last day to change it |
| Payroll match | Pay stub deduction equals the amount you elected |
Benecor's Section 125 cafeteria plan guide explains the plan document in plain terms. If a deduction shows up that you never elected, that is the moment to ask for the paperwork.
How do I ask HR about my health premium deduction?
Send HR a short written request and keep the reply. Copy this email and fill in the brackets.
Employers who want the payroll side of this can read Summit Health Benefits' Section 125 health insurance guide for employers. If you want a Benecor benefits expert to look at your situation, contact Benecor Health.
Sources: IRS Publication 15-B, Employer's Tax Guide to Fringe Benefits (2026); IRS Publication 15, Employer's Tax Guide (2026); IRS General Instructions for Forms W-2 and W-3 (2026); 26 CFR 1.125-4, Permitted election changes (Cornell Legal Information Institute, 2026); Proposed Treasury Regulation Section 1.125-1(c), written plan requirement (2026); KFF, 2025 Employer Health Benefits Survey (2025).
Frequently asked questions
- What is Section 125 health insurance?
- It is health coverage whose premium you pay through your employer's Section 125 cafeteria plan, so the premium comes out before most taxes. Employee-paid accident and health premiums are exempt from income tax withholding, Social Security tax and Medicare tax (IRS Publication 15-B, 2026).
- What does a Section 125 medical deduction on my pay stub mean?
- It usually means your share of the health premium is being taken pre-tax. Labels like medical 125, h125 or caf125 vary by payroll system, so ask HR to list exactly which benefits are in the amount.
- How much does a Section 125 plan save on health insurance?
- On the 2025 average single worker premium share of $1,440 a year, the savings are about $282.96 a year at a 12% federal bracket plus 7.65% FICA (KFF, 2025, and IRS Publication 15, 2026). On the average family share of $6,850, the savings are about $1,346.03 a year.
- Is a cafeteria plan the same as health insurance?
- No. A cafeteria plan is the tax arrangement, and health insurance is the coverage you buy under it. You can have a cafeteria plan with no health insurance, such as a plan that offers only a dependent care account (IRS Publication 15-B, 2026).
- Can I drop my health insurance in the middle of the year?
- Usually only after a qualifying life event that your plan allows, such as marriage, divorce or a birth (26 CFR 1.125-4, 2026). Section 125 elections are generally locked for the plan year, so ask HR for the plan document and your deadline.
- Does Section 125 health insurance show on my W-2?
- Your W-2 Box 1 wages should be lower by the amount of your pre-tax premiums. Box 12 with code DD reports the cost of employer-sponsored health coverage (IRS General Instructions for Forms W-2 and W-3, 2026).
Continue reading
- Section 125 Cafeteria Plan: The Complete Employer Guide (2026) — Section 125 Plan
The authoritative reference. POP, FSA, DCAP, IRS-qualified benefits, FICA recapture math, W-2 reporting, and the five-step employer implementation flow.
- Is Section 125 Pre Tax? What It Skips and What It Does Not — Employee Benefits
Section 125 deductions come out of your pay before income tax, Social Security and Medicare. See what is pre tax, what is not, and what you save.
- Section 125 qualifying life events — Section 125 Plan
Section 125 qualifying life events let employees change benefit elections mid-year. See the IRS-approved events, the consistency rule and how to set the policy.
About the author
Muhammad Mudassir — Co-founder & Health Tech Sales Lead
Muhammad Mudassir, who goes by Moe, is a co-founder and health technology operator focused on Section 125 cafeteria plans and zero-cost employer benefits. He has spent years getting employers enrolled in compliant cafeteria plans, onboarding nationwide workforces into the WoW Health and UnifyWell ecosystems, and translating the mechanics of FICA recapture into language that HR, finance, and ownership can act on.