11.1 Other Insurance: Primary, Excess, Pro Rata & Contribution
Key Takeaways
- An other insurance clause allocates a loss among concurrent policies; it never increases the insured's recovery, because the principle of indemnity caps recovery at the amount of the loss no matter how many policies apply.
- Under pro rata liability each insurer pays the share of the loss that its limit bears to the total of all applicable limits, while under contribution by equal shares each insurer contributes equally until the loss is paid or until its limit is exhausted, after which the remaining insurers continue in equal shares.
- A primary policy pays first from the first dollar above any deductible, while an excess policy attaches only after the underlying limits are exhausted and may never be triggered at all.
- The Personal Auto Policy is primary for a covered auto the insured owns and excess for a non-owned auto, which is the single most tested other insurance rule in personal lines.
- Non-concurrent policies covering different property, periods, or perils are apportioned by the courts rather than by a simple limit ratio, and Texas adjusters should refer genuinely non-concurrent disputes to coverage counsel.
11.1 Other Insurance: Primary, Excess, Pro Rata & Contribution
Quick Reference: When two or more policies cover the same loss, an Other Insurance clause decides who pays what. It never decides how much the insured collects — the principle of indemnity already caps that at the amount of the loss. The three mechanisms the Texas exam tests are pro rata liability (each insurer pays in the ratio its limit bears to total limits), contribution by equal shares (each insurer pays equally until the loss is paid or a limit is exhausted), and the primary/excess relationship (one policy pays first and the other attaches only above it).
1. Why Other Insurance Clauses Exist
Insurance is a contract of indemnity: it restores the insured to the pre-loss position and no further. Without an other insurance clause, a policyholder holding two $100,000 policies on a building could claim $100,000 from each and profit $100,000 from a total loss. That is the exact moral hazard the doctrine of insurable interest and the other insurance condition were built to eliminate.
The clause therefore does two things simultaneously:
- It prevents the insured from profiting from a loss; and
- It allocates the loss among insurers in a predictable way so the insured is paid promptly rather than waiting out an inter-carrier fight.
Adjuster Rule: Discovering other insurance is never a reason to delay the insured's payment. Texas deadlines under TIC §§ 542.055–.057 run regardless of an apportionment dispute with another carrier, and the 18 percent or judgment-rate-plus-five-percent damages of § 542.060 attach to the insurer that missed the deadline, not to the one that owed the larger share. Pay first, apportion second.
2. Pro Rata Liability
The rule: Each insurer pays the proportion of the loss that its limit bears to the total of all applicable limits.
PRO RATA WORKED EXAMPLE
A Houston warehouse sustains a $250,000 covered fire loss.
Three concurrent policies apply:
Insurer A limit .......... $600,000
Insurer B limit .......... $300,000
Insurer C limit .......... $100,000
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Total applicable limits .. $1,000,000
Insurer A: $250,000 x (600,000 / 1,000,000) = $150,000
Insurer B: $250,000 x (300,000 / 1,000,000) = $75,000
Insurer C: $250,000 x (100,000 / 1,000,000) = $25,000
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Total paid to the insured ............... $250,000
The insured recovers the loss ONCE. No policy pays more than its share,
and no insurer pays more than its limit.
Pro rata is the default in property forms and in the Texas homeowners and dwelling forms, where the condition typically reads that the insurer pays "only the proportion of the loss that the applicable limit bears to the total amount of insurance covering the loss."
3. Contribution by Equal Shares
The rule: Each insurer contributes equally until the loss is paid or until an insurer's limit is exhausted. The insurer whose limit runs out drops out, and the remaining insurers continue contributing equally.
This method appears in the CGL and in many liability forms. It favors insurers with low limits, because a small policy contributes the same dollar as a large one until its limit is gone.
CONTRIBUTION BY EQUAL SHARES WORKED EXAMPLE
A $300,000 covered liability loss. Three policies apply:
Insurer A limit .......... $50,000
Insurer B limit ......... $200,000
Insurer C limit ......... $500,000
Round 1: all three contribute equally toward the loss. Insurer A's
limit is the smallest, so A can contribute at most $50,000.
A pays $50,000 and is EXHAUSTED.
Paid so far: $150,000 ($50,000 each). Remaining loss: $150,000.
Round 2: B and C continue in equal shares on the remaining $150,000.
B pays $75,000 (cumulative $125,000, still inside its $200,000 limit).
C pays $75,000 (cumulative $125,000, well inside its $500,000 limit).
FINAL: A = $50,000 B = $125,000 C = $125,000 Total $300,000
Compare the PRO RATA result on the same facts:
Total limits = $750,000
A: 300,000 x (50/750) = $20,000
B: 300,000 x (200/750) = $80,000
C: 300,000 x (500/750) = $200,000
The method chosen changes each insurer's bill dramatically.
Exam Discipline: If the question says "equal shares," start every insurer at the same dollar and drop out the exhausted limits. If it says "pro rata" or "proportion that the limit bears to the total," build the ratio. Candidates lose these questions by applying the formula the question did not ask for.
4. Primary, Excess, and the Order of Attachment
| Layer | When It Pays | Typical Form |
|---|---|---|
| Primary | From the first dollar above any deductible or self-insured retention | CGL, BAP, property, homeowners |
| Excess (specific) | Only after the scheduled underlying limits are exhausted; follows form | Excess liability policy |
| Umbrella | Excess over scheduled underlying and drops down as primary (subject to a self-insured retention) for claims the underlying does not cover | Commercial umbrella |
| Excess by clause | A primary-form policy that becomes excess because its own other insurance condition says so in a given fact pattern | PAP for non-owned autos; CGL for property in someone else's care |
The trap is the fourth row. A policy can be a perfectly ordinary primary policy and still function as excess on a particular claim because its other insurance clause converts it. The classic examples:
- Personal Auto Policy. Coverage is primary for a vehicle the insured owns and excess for a non-owned auto the insured is driving. When a Texas insured borrows a friend's car and causes an accident, the owner's policy pays first and the driver's PAP sits above it. This single rule accounts for a large share of auto other-insurance questions.
- Business Auto Policy. Similar structure: primary for owned autos, excess for hired and non-owned autos, subject to endorsements that can change the order.
- CGL. The insurance is primary except in stated circumstances — notably when the damaged property is in the insured's care, custody, or control under fire legal liability, or when coverage is provided as an additional insured under a written contract that states it is excess.
The Escape Clause Problem
Some forms historically said the policy did not apply at all if other insurance existed — an escape clause. When two policies each contained one, both purported to vanish and the insured was left with nothing. Courts nearly universally refused that result, and modern forms use pro rata, equal shares, or excess language instead. If an adjuster encounters an escape clause in an old or manuscript form, the coverage position is a legal question, not a desk decision.
5. Non-Concurrency
Policies are concurrent when they cover the same property, the same interest, the same perils, and the same period. They are non-concurrent when any one of those differs — different scheduled locations, staggered policy periods, different perils, blanket versus specific limits.
Non-concurrent apportionment cannot be solved with a simple limit ratio, and courts have developed competing approaches. The practical rules for a Texas adjuster:
- Specific insurance is generally primary over blanket insurance on the same property.
- Identify the mismatch explicitly — is it property, peril, period, or interest? — and document it in the file before proposing a share.
- Escalate genuine non-concurrency to coverage counsel, and keep paying the insured while the carriers sort it out.
6. Other Insurance vs. Two Concepts It Is Not
| Concept | What It Actually Does | Not to Be Confused With |
|---|---|---|
| Other insurance | Allocates a loss among concurrent policies covering the same insured | Subrogation |
| Subrogation | Transfers the insured's rights against a legally responsible third party to the insurer after payment | Other insurance |
| Coinsurance | A property valuation penalty for insuring to less than a stated percentage of value | Other insurance; and in health insurance, cost sharing |
One Loss, One Recovery. Whichever mechanism applies, the insured collects the amount of the loss a single time. The other insurance clause determines only the route the money takes to get there — and under Texas law, it never justifies slowing that money down.
A Houston warehouse suffers a $250,000 covered fire loss. Three concurrent policies with pro rata other insurance clauses apply, with limits of $600,000, $300,000, and $100,000. How much does the $300,000 policy pay?
A $300,000 covered liability loss is shared by three policies with limits of $50,000, $200,000, and $500,000 under a contribution by equal shares clause. What does the $50,000 policy pay?
A Texas insured borrows a neighbor's pickup truck and causes an at-fault collision. Both the neighbor and the insured carry Personal Auto Policies. Which policy pays first?
Two policies cover a Texas commercial risk, but one is a blanket policy across four locations and the other is a specific policy on the single damaged building, with different policy periods. What is this situation called, and how should the adjuster proceed?