What Are Combined Single Limits (CSL)?

Last Updated on December 30, 2025

A combined single limit (CSL) auto insurance policy is a way to structure your liability coverage using one dollar amount per accident instead of separate “buckets.” That single limit can be used to pay a mix of bodily injury claims and property damage liability claims, up to the policy limit.

In plain English: with CSL, you don’t have to worry as much about running out of coverage in one category while you still have “unused” coverage in another. It’s typically listed on your policy as a single number (for example, $300,000 CSL or $500,000 CSL) and is usually written as a per-accident limit.

If you want a quick insurer-written explanation of how CSL compares to split limits, NJM has a clear breakdown here: https://www.njm.com/ask/what-are-split-limit-and-combined-single-limit-policies.

Key Takeaways

• A combined single limit (CSL) policy uses one liability limit per accident that can cover bodily injury and property damage in any combination.
• CSL is often easier to understand than split limits because it’s usually shown as a single number (for example, $300,000 CSL) instead of three numbers.
• The main benefit of CSL is flexibility: you’re less likely to run out of coverage in one category (like property damage) while having unused coverage in another.
• CSL isn’t automatically “more coverage”—the total CSL limit still needs to be high enough for serious accidents, and some drivers may still benefit from an umbrella policy.

CSL vs. Split Limits: What’s the Difference?

Split-limit liability breaks your coverage into separate limits, usually shown as three numbers (for example, 100/300/50). Those three numbers commonly represent:

• Bodily injury per person (the most the policy will pay for injuries to any one person)
• Bodily injury per accident (the most the policy will pay for injuries to everyone combined in that one accident)
• Property damage per accident (the most the policy will pay for damage to vehicles/property you hit)

By contrast, a CSL policy typically gives you one total pool per accident for injuries and property damage combined.

Example: $300,000 CSL

Let’s say an at-fault accident leads to $210,000 in medical-related injury claims and $70,000 in vehicle/property damage. With $300,000 CSL, your insurer can generally pay the combined $280,000 (assuming the claim is covered), leaving you within your limit.

Example: 100/300/50 Split Limits

Now look at the same situation with a split policy of 100/300/50. The total “headline” numbers can sound big, but the sub-limits matter:

• If one injured person alone has $160,000 in damages, the $100,000 per-person limit can leave you exposed for the remainder—even if you haven’t hit the per-accident maximum.
• If the crash causes $80,000 in property damage (very possible with modern repair costs), a $50,000 property damage cap can leave you paying the difference out of pocket.

For a state insurance department explanation of split-limit liability (including the meaning of 100/300/50), North Carolina’s DOI has a straightforward consumer guide: https://www.ncdoi.gov/consumers/auto-and-vehicle-insurance/basic-and-miscellaneous-auto-coverages.

Pros of Combined Single Limit Insurance

The biggest advantage of CSL is flexibility. Instead of separate caps for injuries versus property damage, the limit can be applied where it’s needed most in that specific accident.

That flexibility matters because big property damage claims are more common than many drivers realize. Luxury vehicles can easily exceed six figures. For example, Kelley Blue Book lists a 2025 Porsche 911 starting above $120,000 depending on trim and pricing: https://www.kbb.com/porsche/911/2025/. Even “normal” vehicles can generate surprisingly high repair bills due to sensors, cameras, specialized parts, and calibration.

Pros overview:

• More flexibility in how liability dollars get applied after a serious crash
• Less chance of being “underinsured in one bucket” (like property damage) while still having unused coverage in another
• Simpler to read on the declarations page (one number instead of three)
• Can better protect assets when your net worth, savings, and future earnings are meaningful

Cons of Combined Single Limit Insurance

CSL isn’t automatically “more coverage”—it’s a different structure. In some real-world accidents, a split-limit policy can provide more total available money across categories than a smaller CSL limit.

Here’s the common comparison: a $300,000 CSL versus a 100/300/50 split policy. With 100/300/50, you could have up to $300,000 available for bodily injury (subject to the per-person cap) and up to $50,000 for property damage. If an accident produces both major injuries and major property damage, a $300,000 CSL could be less overall protection than a split option with higher combined category limits.

Cons overview:

• Often costs more than a similar split-limit option (pricing varies a lot by insurer and state)
• Not always “more protection” if you choose a CSL limit that’s lower than what a strong split-limit package effectively provides
• May be overkill for drivers with few assets and low exposure (though severe injury claims can still happen to anyone)
• Some claims can be more complex because a single pool of money has to be allocated across multiple injured parties and damages

How CSL Relates to Medical Bills, Lost Wages, and Lawsuits

Liability claims after an at-fault crash can include far more than “the other car’s bumper.” Bodily injury claims commonly include items like medical costs and lost wages. If damages are serious enough, you may also face a lawsuit.

Most auto liability policies include a legal defense component (often called a “duty to defend”), but there are important details and limits to understand—especially if a claim could exceed your coverage. If you’re worried about being sued after a crash, this guide explains what typically happens: https://www.staging.insurancepanda.com/faq/do-i-have-to-hire-a-lawyer-to-defend-me-if-im-sued-over-an-auto-accident/.

Does a CSL Policy Replace Umbrella Insurance?

Not necessarily. Personal umbrella insurance provides extra liability protection above your auto (and often above your homeowners/renters policy too). CSL can reduce the chance that you’re “short” in a single category, but it does not change the basic fact that severe crashes can exceed common auto limits.

What matters most is the total liability limit you carry and your exposure. If you have significant assets, higher income, rental properties, frequent driving, or multiple drivers, umbrella coverage may still be worth a look. This is a helpful read on who tends to benefit most: https://www.staging.insurancepanda.com/faq/should-rich-people-add-umbrella-coverage-to-their-car-insurance-policies/.

Also, umbrellas usually require you to carry certain underlying auto liability limits first. You can often meet those underlying requirements with either a strong split-limit setup or a high CSL—so choose the structure that gives you the best value for your situation.

How to Check Whether You Have CSL or Split Limits

The fastest way is to pull your auto policy’s declarations page:

• If you see three numbers (like 100/300/50), you have split limits.
• If you see one number (like $300,000 or $500,000) labeled “CSL” or “combined single limit,” you likely have a combined single limit.

If you’re unsure, call your insurer or agent and ask: “Is my liability written as split limits or a combined single limit, and is the limit per accident?” It’s a 2-minute question that can prevent expensive misunderstandings.

How to Decide if CSL Is Worth It

CSL is most attractive when you want more simplicity and flexibility—especially if you’re worried about property damage caps or per-person injury caps creating gaps.

CSL is also worth considering if your household has higher risk drivers. New drivers tend to have higher accident frequency, so the “right” liability structure matters even more. If you’re pricing coverage for a household with a teen driver, start here: https://www.staging.insurancepanda.com/7684/cheapest-car-insurance-for-teens/. And while rates often improve as drivers gain experience, it doesn’t always happen automatically at a specific birthday—this explains the age 25 myth: https://www.staging.insurancepanda.com/faq/do-car-insurance-rates-drop-at-age-25/.

Finally, remember that changing your liability structure and increasing limits can affect price. Liability limits are only one piece of the pricing puzzle, though—these are other common reasons premiums rise: https://www.staging.insurancepanda.com/8578/top-10-causes-of-car-insurance-rate-increases/.

FAQs on Combined Single Limit Insurance

Final Word: Buy Enough Total Liability, Then Choose the Structure

Combined single limit coverage can be a smart upgrade because it reduces “coverage bucket” problems and makes your liability protection easier to understand. But CSL only helps if the limit itself is high enough for your real-world risk.

If you’re choosing between CSL and split limits, focus on (1) how much total liability protection you need, (2) whether your biggest risk is per-person injuries or property damage caps, and (3) whether you’ll also carry an umbrella policy. The best setup is the one that gives your household the fewest ways to be financially surprised after a serious accident.