Key Takeaways

• Coinsurance under the 2025 Postal Service Health Benefits (PSHB) program can result in unexpectedly high costs, even for routine medical services.

• Understanding how coinsurance differs from copayments and how Medicare coordination impacts your share of costs is essential to managing your health expenses effectively.

Understanding Coinsurance: Not Just a Technical Term

Coinsurance is the percentage of costs you are required to pay after you’ve met your deductible. Unlike a copayment—a fixed amount—you share a portion of the cost with your insurance plan. Under PSHB in 2025, this percentage can vary significantly depending on the type of service, your provider’s network status, and whether you have Medicare Part B.

For example, many in-network services under PSHB require 10% to 30% coinsurance, but this can increase dramatically if you’re using out-of-network providers. For high-cost treatments like imaging or specialty care, your share of coinsurance can quickly rise into the hundreds or thousands of dollars.

The Numbers for 2025: What You Could Be Paying

In 2025, the PSHB program outlines coinsurance rates that generally fall into these ranges:

• In-Network Services: 10% to 30% coinsurance

• Out-of-Network Services: 40% to 50% coinsurance

These percentages apply after you’ve met your annual deductible, which may range from $350 to $2,000 depending on your selected plan and coverage type (Self Only, Self Plus One, or Self and Family).

Routine services such as lab tests, diagnostic imaging, and even office visits to certain specialists may fall under coinsurance requirements instead of flat copayments. This can create a false sense of affordability—until you see the final bill.

Coinsurance vs. Copayment: Know the Difference

Many PSHB enrollees assume that routine services will always be covered by low, predictable copayments. In reality, some services that feel “routine”—like bloodwork or outpatient procedures—may fall under coinsurance instead.

Here’s how to differentiate:

• Copayment: A fixed fee (e.g., $30 for a primary care visit)

• Coinsurance: A percentage of the total cost (e.g., 20% of a $1,000 outpatient procedure = $200 out of pocket)

If your plan categorizes more services under coinsurance rather than copays, you could be facing far less predictability and higher potential costs.

Routine Services That Might Not Be So Routine

Even services you receive every year could trigger coinsurance charges. Common examples include:

• Annual physical exams with follow-up testing

• Diagnostic imaging (MRIs, CT scans)

• Lab work that goes beyond the preventive category

• Chronic condition monitoring visits

These services might be labeled as preventive but classified as diagnostic depending on what’s ordered and why. That reclassification can be the difference between full coverage and substantial out-of-pocket expense.

Medicare Part B and Coinsurance Under PSHB

If you’re Medicare-eligible, your out-of-pocket costs under PSHB may change considerably based on whether you’re enrolled in Medicare Part B. In many cases, PSHB plans waive or reduce coinsurance when Medicare is the primary payer. This coordination often results in:

• Lower coinsurance percentages

• Waived deductibles

• Reduced prescription drug costs

However, not enrolling in Medicare Part B when required under PSHB rules can remove those benefits entirely. For 2025, Medicare-eligible annuitants who are not enrolled in Part B—unless exempt—may find themselves paying the full coinsurance percentages listed under their plan.

When Coinsurance Becomes a Bigger Problem

Coinsurance might seem manageable when you’re healthy. But when you face multiple services in a short span—like during an illness, surgery, or chronic condition flare-up—those percentages can stack up quickly.

Imagine:

• 20% coinsurance on a $2,500 procedure = $500

• 30% on a $1,000 series of lab tests = $300

• 25% on $800 of imaging = $200

Combined, that’s $1,000 in coinsurance for just a few services, not including your deductible, copayments, or prescription costs.

Don’t Confuse Annual Out-of-Pocket Maximums with Safety Nets

Yes, PSHB plans include out-of-pocket maximums. For 2025, these generally fall within the following limits:

• Self Only coverage: $7,500 (in-network)

• Self Plus One/Family: $15,000 (in-network)

But those caps only apply to covered in-network services. Out-of-network care often has separate, much higher caps—or none at all. And you still must pay until you hit those maximums. That could mean thousands of dollars paid throughout the year before any protection kicks in.

Common Misunderstandings That Lead to High Bills

Many PSHB members are caught off guard by coinsurance because of the following assumptions:

• “Routine means free.”

• “I won’t need expensive services.”

• “The out-of-pocket max will protect me quickly.”

• “If I don’t enroll in Medicare Part B, my plan will still cover most costs.”

These assumptions don’t always hold true in 2025. Especially with new PSHB requirements and the importance of Medicare coordination, your exposure to coinsurance could be much higher than expected.

What to Look for in Your 2025 PSHB Plan Documents

Before you finalize your plan selection or assume you’re protected, take time to check these sections of your 2025 PSHB brochure:

• Summary of Benefits: Look for services with coinsurance vs. copayments

• Cost-Sharing Examples: These give side-by-side costs for services like X-rays or outpatient surgery

• Medicare Coordination Details: This section outlines what costs are waived if you have Medicare Part B

• Out-of-Network Penalties: See what happens if you accidentally use a provider outside your network

Understanding these factors helps you avoid unexpected medical bills and choose a plan that aligns with your health needs and financial situation.

Key Questions to Ask Before Your Next Appointment

To avoid surprise coinsurance charges, consider asking your provider’s office the following questions:

• Is this service considered preventive or diagnostic?

• Will this test or visit fall under a copay or coinsurance?

• Are all providers involved in my care in-network under PSHB?

• Will Medicare Part B cover any portion of this service if I’m enrolled?

Even routine care can carry unexpected financial consequences under PSHB if you don’t ask in advance.

What You Can Do Now to Protect Yourself

Being proactive is your best defense against high coinsurance expenses. Here’s what you should do in 2025:

• Review your 2025 PSHB plan brochure carefully—especially the cost-sharing sections

• Confirm Medicare Part B enrollment if you’re eligible, unless you meet exemption criteria

• Use in-network providers whenever possible

• Get estimates for high-cost services before scheduling

• Track your cumulative out-of-pocket spending so you know where you stand against your maximum

The more you know ahead of time, the better prepared you’ll be to budget and make smart health decisions.

Why You Shouldn’t Ignore the Fine Print This Year

The transition to PSHB in 2025 has introduced new terms, new requirements, and new cost structures. Coinsurance is one of the most misunderstood components—especially because it looks small as a percentage, but can balloon quickly depending on what care you need.

Even if you’re relatively healthy now, you owe it to yourself and your family to understand what your plan really covers. Misjudging coinsurance can cost you far more than expected.

Stay Informed, Stay Covered, and Don’t Guess on Coinsurance

Coinsurance under PSHB in 2025 is not just a line item—it’s a real cost you need to prepare for. Knowing how it works, where it applies, and what affects it (like Medicare coordination) is key to protecting your budget and your health. If you’re unsure about your PSHB options or what your plan really covers, now is the time to talk to a licensed agent listed on this website. Get expert support before your next doctor’s visit turns into an unexpected bill.