Can health insurance deny coverage for pre-existing conditions?

ACA-compliant plans can't. Short-term plans, some excepted benefits and Medigap outside protected periods can.

Can my employer plan exclude a pre-existing condition?

No. Group health plans can't apply pre-existing condition exclusions under the ACA.

Does Medigap cover pre-existing conditions?

During your Medigap open enrollment period you can't be turned down or charged more for health, but a policy can still impose a waiting period of up to six months unless you had prior creditable coverage.

What counts as a pre-existing condition in a short-term plan?

It's defined in the policy, often as anything diagnosed, treated or with symptoms within a look-back period before coverage began. Read the exact wording.

Pre-Existing Condition Denial: Is It Legal and What to Do

By AppealFlow editorial•5 min read•Published October 2026

For most health plans, a pre-existing condition denial is not allowed: the ACA bars ACA-compliant individual, small group and employer plans from refusing coverage, charging more, or excluding care because of a health condition you had before enrolling. Short-term plans, fixed-indemnity policies, some grandfathered individual policies and Medigap outside protected periods can still use pre-existing condition rules. If you're on an ACA-compliant plan, appeal and cite the ban; if not, check the policy terms and state law.

What Does the ACA Ban?

Key Takeaway: These rules cover most people with job-based or marketplace insurance.

Since 2014, the ACA (Public Health Service Act section 2704) bars pre-existing condition exclusions in group health plans and non-grandfathered individual coverage. Plans can't refuse to sell you a policy, can't charge more because of health status, and can't exclude benefits for a condition that started before your coverage began.

Which Coverage Can Still Exclude Conditions?

Key Takeaway: Check what kind of plan you actually have.

Short-term, limited-duration insurance
Fixed-indemnity, critical illness and other excepted benefits
Grandfathered individual policies bought before March 23, 2010 (rare now)
Medigap policies bought outside your open enrollment period or a guaranteed-issue situation, which may have a waiting period of up to six months for pre-existing conditions
Travel insurance and some health care sharing ministries, which aren't insurance

How Do I Appeal a Pre-Existing Condition Denial?

Key Takeaway: Start by naming your plan type.

Find the plan type on your card, policy or Summary of Benefits and Coverage. Words like "short-term" or "limited-duration" matter.
If it's an ACA-compliant plan, appeal and state that pre-existing condition exclusions are prohibited under PHSA 2704.
If the plan is short-term, read the definition of pre-existing condition and the look-back period; denials sometimes stretch the definition beyond the policy wording.
Ask for the records they relied on to decide the condition existed before coverage.
Draft the letter with the free appeal letter generator and file a complaint with your state insurance department if needed.

What If I Need Better Coverage?

Key Takeaway: You may be able to switch.

You can buy an ACA marketplace plan during open enrollment, or within 60 days of a qualifying life event. Losing other coverage usually counts, but voluntarily dropping a short-term plan may not. See whether you can change your health insurance for timing.

Related Guides

Frequently Asked Questions

Sources

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Disclaimer: This article is for educational purposes only and does not constitute medical, legal, or financial advice. Plan terms, state laws, and federal rules vary and change. Check your plan documents and denial notice, and consider a licensed professional or your state consumer assistance program. See our full disclaimer.