Large Companies Often Insure Themselves Through a Subsidiary They Own
A captive insurer is an insurance company owned by the business it insures. It converts an insurance purchase into a financing decision and keeps the profit that an outside insurer would have earned.
What a Premium Actually Contains
An insurance premium is not just the expected cost of claims. It includes the insurer expenses, the cost of holding capital against the risk, a margin for uncertainty, and profit.
For risks that are genuinely unpredictable, all of that is worth paying. For risks a large company faces regularly and can forecast well, a substantial part of the premium is buying certainty the company may not need.
The Captive Structure
A captive insurer is a licensed insurance subsidiary owned by the parent, whose main business is insuring the parent operations. The parent pays premiums to it, it holds reserves, and it pays claims.
Because the captive is owned by the parent, underwriting profit stays inside the group instead of going to a third party. Reserves are invested and the investment income also stays inside.
A captive does not eliminate the risk. It stops paying someone else to carry a risk the company was well placed to carry itself.
Why It Is Not Simply Self Insurance
A company could just pay losses as they arise and skip the structure entirely. The captive exists because the formal arrangement provides things informal self insurance does not.
| Benefit | Why the structure is needed |
|---|---|
| Access to reinsurance | Reinsurers deal with insurers, not corporates |
| Tax treatment of reserves | Premiums may be deductible when paid |
| Formal claims discipline | Losses are measured and priced properly |
| Evidence of cover | Contracts and regulators often require a policy |
Reinsurance access is the most practically important. A captive can buy excess of loss protection above a retention level, so the group keeps predictable losses and transfers the catastrophic tail. That combination is usually far cheaper than buying full cover commercially.
The Discipline Effect
An underrated benefit is behavioural. When business units pay real premiums to the captive, priced according to their loss experience, safety improves. A division with poor claims history pays more, and that shows up in its own results.
Informal self insurance loses this entirely, because losses disappear into general costs and nobody is accountable for them.
Where It Goes Wrong
The failure mode is undercapitalisation. A captive is a real insurance company and must hold reserves adequate for its liabilities. A parent that treats it as a cash source, or sets premiums too low to make group results look better, has created an entity that cannot pay claims when they arrive.
Tax authorities also scrutinise these arrangements closely. The deduction depends on the arrangement being genuine insurance, which requires real risk transfer and risk distribution. Structures set up primarily for tax benefit, without genuine insurance substance, have been challenged successfully.
There is also a concentration problem the parent may not notice. A captive insuring only its parent has no diversification at all, which is the opposite of how insurance is supposed to work. That is acceptable when the parent is large and the risks are predictable, and dangerous when neither holds.
Who Should Use One
The arithmetic favours companies with large, frequent, predictable losses, enough capital to absorb volatility, and long enough horizons that averages actually arrive. Trucking fleets, large property portfolios, and employers with substantial workers compensation exposure are typical.
It is a poor fit for smaller companies, where a bad year cannot be absorbed and where the fixed costs of running a licensed insurer overwhelm the savings.
The Bottom Line
A captive insurer keeps the margin an outside insurer would have earned on risks the company can predict and absorb, while buying reinsurance for the tail it cannot. It works when the company is genuinely large enough to carry the volatility, and it becomes a liability disguised as a saving when the reserves are set to flatter results rather than to pay claims.