Updated October 1, 2026.
Direct answer: Reinsurance is how primary insurers transfer part of the risk they sold to policyholders onto professional reinsurers through treaty or facultative contracts—proportional shares (quota share, surplus share) or non-proportional layers (excess of loss, aggregate excess of loss)—and sometimes onward via retrocession. Policyholders do not buy reinsurance directly, but it governs how much capacity carriers can deploy, what they charge, and what happens to recoveries if a carrier fails.
Most buyers never see a reinsurance slip. They should still understand the chain: every large property or liability program a carrier writes is usually reinsured in the background. When that backstop shrinks or gets expensive, the primary market tightens first. For a wider map of the field, see the Reinsurance: The Complete Professional Guide (2026).
The Reinsurance Transaction
Two insurers, one insured. The cedent (ceding company) has already promised to pay the policyholder under the primary policy. It pays a reinsurance premium to the reinsurer (assuming company), which agrees to fund defined claim recoveries. Triggers come from the treaty or facultative certificate: proportional treaties pay a set percentage of every qualifying loss; non-proportional covers pay when losses pierce an attachment point or exhaust a retention.
Privity runs cedent-to-reinsurer. The policyholder is not a party to the reinsurance contract. If the cedent becomes insolvent, reinsurance recoveries typically belong to the estate for distribution through the insolvency process—not a separate check from the reinsurer to each policyholder.
Definition — Cut-through endorsement
A provision—sometimes endorsed on the primary policy or referenced in the reinsurance treaty—that lets the policyholder pursue named reinsurers directly if the cedent cannot pay, usually after insolvency. Availability varies by market and line; it is more common on large commercial and specialty placements than on standard homeowners business.
Carriers buy reinsurance for four practical reasons. Capacity lets a cedent write more gross premium while keeping net retention within capital limits. Catastrophe protection caps net loss from a single event or a bad season. Financial stability smooths results when loss years cluster. Portfolio management trims unwanted concentrations after cession.
Treaty vs. Facultative Placement
Treaty reinsurance is automatic cession of defined business under annual or multi-year terms. The reinsurer prices the cedent’s underwriting and portfolio mix; it does not re-underwrite each certificate at bind. Treaties may be proportional (sharing premium and loss from dollar one on ceded policies) or non-proportional (responding only above retentions).
Facultative reinsurance is placed one risk at a time. The cedent submits an account—often high total insured value, heavy catastrophe exposure, or an occupancy outside treaty eligibility—and negotiates shares with facultative markets. When facultative support disappears, primary carriers cannot always hold the full limit; buyers see declinations, reduced limits, or referral to residual markets.
Treaty design—attachment, hours clause, reinstatements, exclusions—is where cedents and reinsurers allocate tail risk. See Quota Share Reinsurance vs Excess of Loss (Treaty Structures) for common forms.
Proportional vs. Non-Proportional Structures
Proportional (pro rata) reinsurance
Quota share cedes a fixed percentage of every policy in a class—simple capacity relief, but the cedent gives up the same margin on good business as on bad. Surplus share cedes amounts above a per-risk retention (the “line”), preserving more profitable small accounts while offloading peak limits on large properties.
Non-proportional reinsurance
Per-occurrence excess of loss attaches above a retention on a single event. Aggregate excess of loss attaches after ceded losses stack across many events in a treaty year—useful when frequency, not one headline cat, threatens surplus.
Cedents stack layers: quota or surplus for baseline sharing, cat XL for peak per-event loss, aggregate XL for year-long accumulation. Layer design tied to net retention and peak zones is covered in Catastrophe Portfolio Management: Accumulation Control, PML Management, and Reinsurance Design.
Retrocession
Retrocession is reinsurance purchased by a reinsurer to cede part of its assumed portfolio to other reinsurers (retrocessionaires). It spreads peak zones and single-risk accumulations and can free capacity for the next underwriting season. Policyholders still deal only with their carrier unless direct-access clauses exist; failures at any link flow through contracts and insolvency law.
Alternative Capital in the Reinsurance Stack
Catastrophe bond issuance reached roughly $18 billion across 83 transactions in the first half of 2026, with outstanding cat bond market size near $65.6 billion at mid-year (Artemis)—capital that often backs reinsurance and retrocession layers. Parametric and index-based structures pay on objective triggers instead of indemnity adjustment on each policy. When alternative capital is eager, reinsurance terms soften; when investors demand higher spreads, cedents pay more for the same net protection. See Parametric Insurance and Index-Based Risk Transfer for index triggers vs indemnity reinsurance.
Why Reinsurance Matters for Policyholders
Reinsurance premium is a real cost inside primary rates—especially on catastrophe-exposed property. Cedents cannot absorb a permanent step-up in reinsurance pricing without moving primary rates, deductibles, or underwriting guidelines. In a hard market, tighter reinsurance shows up as non-renewals, reduced capacity in coastal and wildfire-prone counties, and more business in state residual plans.
Reinsurance also shapes outcomes when the carrier is stressed: recoveries fund claim payments and surplus restoration. When the carrier fails, understanding whether reinsurance is collectable only by the estate—and whether cut-through exists—belongs in the same review as primary policy language in How to Read an Insurance Policy.
Buyers cannot negotiate treaty attachments, but they can influence facultative exposure (values reported, loss control, deductible selection) and choose carriers with stable net retentions. That diligence matters most where one event can drive both a property claim and a carrier balance-sheet shock.
Frequently Asked Questions
What is reinsurance and how does the basic transaction work?
Reinsurance is insurance bought by a primary carrier (the cedent) from another insurer (the reinsurer) to transfer part of the risk the cedent assumed from policyholders. The cedent pays a reinsurance premium; the reinsurer pays recoveries when ceded claims meet the contract’s triggers—either a fixed share of every loss (proportional) or losses above a retention (non-proportional). The policyholder remains the cedent’s customer. Under ordinary privity rules, the reinsurer owes the cedent, not the policyholder; if the cedent fails, recoveries flow to the estate unless a cut-through or similar arrangement applies.
What is the difference between treaty and facultative reinsurance?
Treaty reinsurance is a standing agreement: the cedent automatically cedes defined classes of business and the reinsurer accepts the portfolio under treaty terms without underwriting each policy individually. Facultative reinsurance is placed one risk at a time—the cedent submits a specific account, the reinsurer underwrites it, and participation is negotiated case by case. Treaties carry most premium volume; facultative covers oversize exposures, unusual hazards, and risks excluded from treaty programs.
How do proportional and non-proportional reinsurance differ?
Proportional reinsurance splits premium and losses between cedent and reinsurer at a set percentage—quota share cedes a fixed share of every policy in a class; surplus share cedes amounts above a line the cedent retains per risk. Non-proportional reinsurance pays only when losses exceed thresholds—per-occurrence excess of loss caps the cedent’s retention on a single event; aggregate excess of loss responds when many smaller losses or an accumulation breach an annual attachment. Primary carriers combine both to manage net retention, surplus strain, and catastrophe peaks.
What is retrocession?
Retrocession is reinsurance of reinsurance. A reinsurer that has assumed large or concentrated exposures cedes part of its portfolio to other reinsurers (retrocessionaires) to limit its own net loss, meet internal capital targets, or diversify peak zones. Retrocession sits behind the primary policy chain; policyholders still deal only with their carrier unless special direct-access clauses exist.
Why should property owners and risk managers care about reinsurance?
Reinsurance cost and capacity sit inside primary pricing and underwriting appetite. When reinsurers tighten terms or raise prices, cedents retain more net risk, raise rates, restrict new business in concentrated catastrophe areas, or exit lines they cannot reinsure economically—policyholders see that as higher premiums, tougher deductibles, or fewer carrier options. Reinsurance also affects solvency: standard recoveries run to the cedent, so understanding cut-through and guaranty-fund limits matters for large commercial placements.
Can a policyholder collect directly from a reinsurer after a loss?
Usually no. The reinsurance contract is between cedent and reinsurer; the policyholder’s claim runs against the primary policy. A cut-through endorsement (where available) can grant the policyholder a direct recovery right against named reinsurers if the cedent becomes insolvent. That is uncommon on standard personal lines and more relevant on large commercial or specialty placements where buyers negotiate security.