Most explanations of self-funded health insurance are written by people who already know what a “specific attachment point” is, and they use phrases like “aggregate reconciliation” and “run-in period” without blinking. If you’re a business owner trying to figure out whether self-funded insurance would work for your company, that writing is not helpful.

No jargon here. No assumed knowledge. Just a step-by-step walk-through of what self-funded health insurance actually is, who does what, what you pay, and how to tell if it would be a good fit for your business.

The one-sentence version

Instead of paying an insurance company a fixed fee every month to cover your employees’ medical claims, you pay the claims directly when they happen, and you buy a separate insurance policy that kicks in if any single claim gets catastrophically expensive.

That’s it. Everything else is details.

The slightly-longer version

In a traditional (fully-insured) plan, this is what happens every month:

  1. You write a check to the insurance company.
  2. The insurance company puts your money in a big pool with everyone else’s money.
  3. The insurance company pays claims out of the pool.
  4. Whatever’s left over is the insurance company’s profit.
  5. Next year, they raise your premium.

In a self-funded plan, this is what happens every month:

  1. You put an amount roughly equal to your expected claims into an account your company controls.
  2. A company called a third-party administrator (TPA) processes claims and pays them out of that account.
  3. You pay the TPA a fee for their work.
  4. You pay a stop-loss premium to another insurance company that will reimburse you if any claim (or all claims together) exceeds a set threshold.
  5. Anything left in the account at the end of the year stays with your business.

The key difference: in fully-insured, the savings from a healthy year go to the insurance company. In self-funded, they stay with you. And your catastrophic risk is capped by the stop-loss policy, not left unlimited.

Who does what (the cast of characters)

When you’re learning about self-funded plans, it helps to have a quick map of the players.

Your company. You’re the sponsor. You fund the claims account, you make the strategic decisions about plan design, and you keep the savings when things go well.

The third-party administrator (TPA). This is the company that actually runs the plan day to day. They process claims, handle the ID cards, operate the network, answer employee calls, and generate reports. Most TPAs are affiliated with a major carrier (Aetna, Cigna, BlueCross, UnitedHealthcare) or are independent firms. Your employees can’t tell they exist. They just see the logo on their ID card.

The stop-loss carrier. This is the insurance company that sells you the stop-loss policy. They take on the catastrophic-risk piece that you don’t want to. They’re also the company that writes the check when one of your employees has a huge claim.

Your benefits advisor. This is your broker, consultant, or fiduciary advisor: the person who helps you design the plan, shop the stop-loss policy, and make informed decisions. Good ones are paid a flat fee and are aligned with lowering your total costs. Commission-based advisors have an incentive to keep you on fully-insured.

Your employees. They use the plan like they would any other health plan. Show the ID card, pay the copay, file claims. The self-funded structure is mostly invisible to them. As covered in Is Self-Funded Health Insurance Good for Employees?, the differences they notice are usually minor and frequently positive.

What you actually pay every month

In a self-funded plan, your total monthly cost is the sum of three things:

1. The claims fund. This is money set aside to pay claims as they come in. It’s sized based on what your team’s expected claims are for the year, determined by looking at historical claims data or demographics. Think of this as “pre-funding” your healthcare spend.

2. Administrative fees. The TPA charges you a per-employee-per-month (PEPM) fee to run the plan. The fee scales with group size and scope: smaller groups pay more per employee, larger groups pay less.

3. Stop-loss premium. The stop-loss carrier charges you a monthly premium for the coverage that caps your catastrophic exposure. This is typically the smallest of the three categories but the most important for risk management.

When all three are added together, the total monthly cost for a healthy self-funded group runs below what a fully-insured plan would cost for the same coverage. The exact savings depend on group demographics, claims experience, and how the stop-loss is structured.

A key point: those three pieces are separable. You can shop each of them. In a fully-insured plan, they’re bundled and opaque. You pay one premium and you don’t know how much of it went where. That opacity is one of the biggest reasons fully-insured plans cost more over time.

How stop-loss actually works

Stop-loss is the part that makes self-funding safe, and it’s the part most people find counterintuitive at first.

You set a threshold called the specific attachment point, a dollar amount you and your advisor choose when you buy the policy. If any one employee’s medical claims exceed that amount in a plan year, the stop-loss insurance company reimburses your plan for everything above the threshold.

Illustrative example: imagine your specific attachment point is $75,000 and one employee has a serious surgery that generates $300,000 in claims. Your plan pays the first $75,000 from the claims fund. The stop-loss carrier reimburses the remaining $225,000. You’re out $75,000, not $300,000.1

There’s also aggregate stop-loss, which protects against too many moderate claims piling up across your whole group. It kicks in when your total group claims exceed an expected ceiling defined as a percentage above projected annual claims. Your worst-case for the entire year is capped.

Put those two together, and self-funding stops looking like gambling. It looks like a structured financial product with a defined downside.

What Is Stop-Loss Insurance walks through this in more depth, and Stop-Loss Insurance Explained with Real Examples shows the numbers play out in specific scenarios.

The whole reason self-funded insurance works for small businesses is stop-loss. Without it, you’d be taking on unlimited risk. With it, you’re taking on a defined, bounded risk — and keeping the upside when things go well.

What about a bad year?

This is the question everyone asks.

In a “bad year,” meaning your claims come in higher than expected, a few things happen:

  1. Your claims fund gets drained faster than planned.
  2. If claims stay under the stop-loss thresholds, you end up paying more than you would have under fully-insured for that year.
  3. If claims hit the stop-loss thresholds, the stop-loss carrier covers the excess and your worst-case outcome is the total of your monthly payments plus the attachment point.
  4. At the next renewal, your stop-loss premium and expected claims amount will be re-priced based on the new data.

The worst-case math is a capped loss. In a fully-insured plan, the carrier absorbs the bad year and spreads it across their whole book, but they’ll price you up at renewal to recover it. The difference is that in fully-insured, a bad year shows up as compounding rate increases over multiple years. In self-funded, a bad year is a defined financial loss sized to your stop-loss structure, and then it’s done.

Over a multi-year window, for a healthy group, self-funded almost always comes out ahead. Over a one-year window for an unlucky group, it may not.

When self-funded makes sense

The simple version of the fit rubric:

  • Company size of 50+: self-funded is worth modeling seriously
  • Company size of 10-50: level-funded is usually the better entry point, and it’s essentially self-funding with training wheels
  • Company size under 10: fully-insured is the only realistic option in most cases

On top of size, the other fit factors are:

  • Your team is roughly average-health or better
  • Your cash flow can absorb some month-to-month variability (or you’re using level-funded to avoid that)
  • You’re willing to engage with your claims data at least quarterly
  • You have a benefits advisor who is actually on your side (not paid on commission off your premiums)

If all of those apply, self-funded is probably saving you real money versus your current fully-insured plan.

What to do next

If this is your first pass at self-funding, the most useful next move is one of two things.

Option A: Get your claims data. Even before you change anything, ask your current carrier for your claims data. You’re entitled to it in many states, and even a high-level summary (claims by month, top cost drivers, large claims over a threshold) changes the conversation.

Option B: Get a level-funded quote alongside your fully-insured quote at renewal. Ask your broker to present both. Compare the total monthly cost, the stop-loss structure, and the surplus provisions. If the numbers are favorable, try level-funded for a year. At the end of that year, you’ll have your own claims data and can make a more informed decision about whether to stay on level-funded or move to fully self-funded.

Either path starts the process of getting visibility into what’s actually happening with your healthcare spend. Visibility is the prerequisite to every other decision.

Putting it together

Self-funded health insurance sounds complicated because the industry likes it that way. In practice, it’s a straightforward trade: instead of paying an insurance carrier a premium that bundles everything into one opaque number, you pay the pieces separately and keep the savings when things go well. Stop-loss covers you if they don’t.

For healthy groups of 25 employees and up, self-funded or level-funded is almost always a better deal than the fully-insured plan most brokers will try to renew you into. You just have to be willing to look.

Want a plain-English walkthrough of your options? Download The Rate Shock Survival Guide for a step-by-step framework for evaluating self-funded and level-funded alternatives to your current plan. Get your copy here.

Footnotes

  1. Illustrative example, not a specific quote. Actual stop-loss attachment points, premiums, and claims outcomes vary by group size, demographics, and which carrier is writing the coverage. ↩