Why Is My Coinsurance Percentage Different Depending on the Type of Service?

By The Penny Plan Editorial Team Published July 13, 2026 6 min read

An explanation of benefits shows a 20 percent share for one visit and a 40 percent share for another, both under the same health plan, and it’s natural to assume something was billed wrong when really the plan may have simply been designed that way from the start.

In a nutshell

Health plans commonly assign different coinsurance percentages to different categories of care, such as primary care, specialist visits, outpatient surgery, and emergency services, as a deliberate part of how the plan is structured. This isn’t an error or inconsistency; it reflects choices the plan design made about which categories of care to encourage with lower cost-sharing and which to price higher. Every employer’s plan and every insurer’s plan can set these percentages differently, so there isn’t one standard breakdown to compare against.

Why plans split coinsurance by category

Insurers and employers generally design cost-sharing to nudge behavior toward certain kinds of care, similar to how a plan’s out-of-pocket maximum is structured to cap total exposure once spending crosses a threshold. Lower coinsurance on primary care and preventive visits is a common design choice meant to encourage people to seek routine care rather than delaying it, since delayed care can sometimes lead to more expensive treatment later. Higher coinsurance on emergency room visits or out-of-network care is often intended to reflect the higher underlying cost of that care or to encourage using an in-network provider or a lower-cost setting when the situation allows for it.

Common categories that get different rates

Where to actually find the breakdown

The summary of benefits and coverage document that comes with every plan lists coinsurance percentages by category, and it’s the most reliable source since verbal descriptions from a provider’s office don’t always match the plan’s actual terms. Because surprise billing protections and category definitions can vary by plan and by state, checking the specific document for a given plan year is more useful than relying on a general rule of thumb learned from a previous employer’s plan.

Why this varies so much between employers

Employers that sponsor health plans often choose from several coinsurance structures offered by an insurer, or negotiate their own structure entirely, which is why two people working at different companies but using the same insurance carrier can have noticeably different coinsurance percentages for the same type of care. None of this is standardized at a national level, so comparing a plan’s terms to a friend’s or a previous employer’s plan isn’t a reliable way to predict what a current plan actually covers.

Worth remembering

Different coinsurance percentages across categories of care are usually intentional design choices rather than errors, generally aimed at encouraging preventive and lower-cost care while assigning higher cost-sharing to more expensive categories like emergency visits. Reviewing the actual plan documents for a specific year remains the most reliable way to understand what a given category will actually cost, since these percentages differ meaningfully from one employer’s plan to the next.