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How to choose an insurance plan

Key points: 

  • Know your family’s medical needs and past use of health plan benefits before choosing a healthcare plan.
  • Compare benefits, drug formulary lists, and provider networks (if applicable) across several plans to help determine which one offers the best balance of price versus coverage for you.
  • Choose you Medicare options carefully, especially if you are on immunoglobulin replacement therapy.

How to choose an insurance plan

When it comes to health insurance, you need to be your own advocate—and that starts with asking questions. It’s your responsibility to understand your plan, no matter how you and your family get coverage. You’ll want to find a plan that’s right for you because it can have a huge impact on your health and finances.

Choosing the right health insurance plan can be a daunting task. It’s crucial to understand your plan's details and make an informed decision to ensure both your health and finances are protected. Always review a plan's summary of benefits, drug formulary list, and provider network directory.

Questions to ask before deciding on a health plan:

  • What is the premium?
  • What is the out-of-pocket maximum?
  • What are the deductibles?
  • Is the deductible included in the out-of-pocket maximum, or is it in addition to the maximum?
  • How is immunoglobulin (Ig) therapy covered?
  • Do you have coinsurance or a flat copay for treatments and services you are likely to need?
  • Do you have options for the site of care?
  • Are your physicians in the plan's network?
  • Are there out-of-network benefits?
  • Does the plan have a copay accumulator?

Here are definitions for common health insurance terms. An example health insurance plan might have a premium of $395/month, a $2000 deductible, a $40 copay for office visits, 20% coinsurance for imaging tests, and a $3000 out-of-pocket maximum. The timeline shows a person's out-of-pocket costs and how each item applies for each month during the year with the example plan.

Health insurance terms

Choosing a private health plan

Unexpected medical needs can be costly and unpredictable, so it's important to understand the costs associated with your health plan based on your family's known health situations.

  1. Complete the Personal Health Experience Stat Sheet to identify and quantify the health services you and your family used in the previous 12 months. This provides a list of benefits your new plan should include.
  2. Ask your human resources representative, insurance agent, or marketplace agent to provide the following documents for each health plan you are considering:
    • Benefit summary: an easy-to-understand summary of a health plan's benefits and coverage.
    • Drug formulary: a list of prescription drugs covered by the health plan.
    • Provider network directory: a list of providers contracted with the health plan to provide healthcare services.
    • Health savings account (HSA) or flexible spending account (FSA) details, if applicable.
  3. Complete the Health Plan Cost Comparison Worksheet to evaluate your potential plan costs based on your prior year's medical experience.

Additional tips to consider:

  • Ask your human resources/benefits administration department, broker, or the health plan's customer service representative if you have questions about your options.
  • You may have the choice between EPO, HMO, POS, or PPO plan types. Consider the pros and cons of each type of plan.
    • Exclusive provider organization (EPO): A managed care plan in which services are covered only if you go to doctors, specialists, or hospitals in the plan’s network (except in an emergency).
    • Health maintenance organization (HMO): An insurance plan that usually limits coverage to care from doctors who work for or contract with the HMO. Generally, it won’t cover out-of-network care except in an emergency and may require you to live or work in its service area to be eligible for coverage.
    • Point-of-service (POS): A type of plan in which you pay less if you use doctors, hospitals, and other healthcare providers that belong to the plan’s network. POS plans may also require you to get a referral from your primary care doctor to see a specialist.
    • Preferred provider organization (PPO): A type of health plan that contracts with medical providers, such as hospitals and doctors, to create a network of participating providers. You pay less if you use providers who belong to the plan’s network. You can use doctors, hospitals, and providers outside of the network for an additional cost.
  • Check enrollment dates with your employer or the Affordable Care Act (ACA) marketplace [2].

Figure out which benefits you use

Our worksheet helps you track the healthcare services you and your family used over the previous 12 months. This information can help you determine what health insurance benefits are important for you.

Download worksheet

Compare costs and benefits

Download our worksheet to help you compare costs and benefits based on the services you and your family use across up to three different health insurance plans.

Download worksheet

Choosing a Medicare plan

Similar to choosing a private insurance plan, you need to do a thorough evaluation of your choices to determine the Medicare plan that works best for you. Medicare is broken into several parts:

  • Part A: Original Medicare that covers inpatient hospital stays, skilled nursing facilities, hospice care, and some home healthcare.
  • Part B: Optional part of original Medicare that covers doctor’s visits, preventative care, medical tests and imaging, and some prescription drugs, including immunoglobulin (Ig) replacement therapy for certain PI diagnoses.
  • Part C: Also known as Medicare Advantage coverage; these privately run plans must cover Part A and Part B services and benefits but can impose their own rules, including preferred provider networks, drug formularies, cost-sharing, prior authorization, step therapy, and referral requirements.
  • Part D: Optional prescription drug coverage, which may include Ig replacement therapy for PI diagnoses that are not covered under Part B. Check with the specific plan for details.
  • Parts F & G: Optional supplemental coverage known as Medigap coverage.

During enrollment, you must choose between either original Medicare (Parts A & B) or a Medicare Advantage plan (Part C). Only those enrolled in original Medicare who do not have other, secondary insurance can opt to purchase Medigap coverage (Part F or G). If you opt for a Medicare Advantage plan, you are not eligible to purchase Medigap coverage.

Those who purchase Part D drug plans or Medicare Advantage plans with drug coverage can also enroll in the Medicare Prescription Payment Plan [3]. People who use this payment option will receive a monthly bill for their prescriptions covered under Part D from their plan instead of paying the pharmacy directly when the prescriptions are filled. The plan is intended to help seniors manage their monthly expenses, but it does not lower overall drug costs.

Since Medicare plans vary from state to state and even by counties within a state, you need to research the plans you are eligible for. Contact your State Health Insurance Assistance Program (SHIP) [4] to find trained counselors who can tell you which plans you are eligible for and assist you in finding the answers to your coverage questions.

Medicare eligibility and enrollment

Most people become eligible for Medicare when they turn 65 years old. If you are already collecting Social Security at age 65, you are automatically enrolled in Medicare. If not, you must enroll during a 7-month “initial enrollment” period to avoid paying a penalty. The initial enrollment window includes the three months before you turn 65, the month of your 65th birthday, and the three months after you turn 65.

If you miss your initial 7-month enrollment window, you can enroll with a penalty from January 1 through March 31 each year, which is known as the “general enrollment” period. There are also special enrollment periods for those in specific situations to enroll without a penalty.

To enroll in Medicare due to disability, you must qualify for and collect Social Security disability benefits for two years before you are eligible.

After your first enrollment, there is an “open enrollment” period when you may join, switch, or drop Medicare plans. It takes place each year from October 15 to December 7, with coverage starting January 1.

Coverage for Ig therapy

Under original Medicare, coverage for Ig therapy depends on your specific diagnosis. For certain PI diagnostic codes, Ig therapy, whether intravenous (IVIG) or subcutaneous (SCIG), is covered under the Part B medical benefit at 80% with no out-of-pocket maximum. This Part B coverage includes the supplies and nursing necessary for home IVIG, if needed. Other insurance or a Medigap plan (Part F or G) is required to cover the remaining 20%.

For all other PI diagnoses, Ig therapy is covered under Part D. Part D plans have a set out-of-pocket maximum each year. For 2026, that maximum is $2,100.

Another option is a Medicare Advantage plan (Part C), which is sold as an “all-in-one policy” and acts more like private insurance. Part D drug coverage may be included in Medicare Advantage plans, but sometimes it must be bought separately as a stand-alone Part D plan. Medicare Advantage plans decide whether your Ig therapy is billed through Part B or Part D.

Patients with Medicare Advantage plans have reported that most have a 20-30% coinsurance for Ig therapy. If you choose a Medicare Advantage plan, you are not eligible to obtain a secondary Medigap policy. Examine your Medicare options closely if you are on Ig therapy because Medicare Advantage plans may be more costly.

Medicaid eligibility and enrollment

You may qualify for free or low-cost healthcare through Medicaid based on income and family size. Eligibility rules vary from state to state. In all states, Medicaid provides health coverage to some children, parents, pregnant women, elderly people with certain incomes, and people with disabilities. Some states have expanded their Medicaid programs to cover other adults below a certain income.

There are two ways you can apply for Medicaid:

  • Directly with your state at your local county job and family service office.
  • Through the health insurance marketplace.

References

  1. Welcome to the Health Insurance Marketplace®. In: HealthCare.gov [Internet]. [cited 6 Jan 2026]. Available: https://www.healthcare.gov/.
  2. Centers For Medicare Medicaid US. What’s the Medicare Prescription Payment Plan? [cited 6 Jan 2026]. Available: https://www.medicare.gov/prescription-payment-plan.
  3. Get Medicare Help from Your Local SHIP Program. In: State Health Insurance Assistance Programs [Internet]. 14 Jan 2025 [cited 6 Jan 2026]. Available: https://www.shiphelp.org/.

Ask IDF

Getting answers can help create peace of mind. Ask us anything and we’ll consult with experts.

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Do you have information to help me select a health insurance plan to cover my needs?

Selecting a health insurance plan can be a challenging process. Basic information to navigate insurance is available for the PI community.

Answers to specific questions, relative to cost and generally covered benefits, can be found by reviewing a plan’s summary of benefits, drug formulary list, and provider network directory, or by contacting the insurance company. When speaking to an insurance representative, you should be able to receive answers to all of your questions. If not, ask to speak to someone who can answer them.

While this is often considered a tedious process, it is one of the most important steps you can take to ensure that a plan meets your needs. It is better to know everything you can about your plan before you select it than to find problems and hidden costs after you have made a decision. Please remember, it is okay to ask questions until you receive answers when communicating with insurance representatives.

Are prior authorizations required for Ig therapy?

Yes, prior authorizations are required for Ig therapy. These can take anywhere from a couple of days to a few months. Insurance companies require re-authorizations, including updated lab work and clinical notes (from an office visit) every 6-12 months. Some insurance companies are becoming stricter and require this every 1-3 months. 

If you have further questions or are diagnosed with PI and looking for more support, please reach out to us at 410-321-6647.

Filing appeals and complaints

If your insurer denies a claim, you have the right to appeal. You can also consider filing a complaint.

Know your rights
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This page contains general medical and/or legal information that cannot be applied safely to any individual case. Medical and/or legal knowledge and practice can change rapidly. Therefore, this page should not be used as a substitute for professional medical and/or legal advice. Additionally, links to other resources and websites are shared for informational purposes only and should not be considered an endorsement by the Immune Deficiency Foundation.

Adapted from the IDF Patient & Family Handbook for Primary Immunodeficiency Diseases, Sixth Edition.  
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