Guide 6 · sharing a captive

Group captives and risk retention groups: sharing the vehicle

Not every business needs its own captive. Group captives and risk retention groups let several businesses share one, spreading the risk and the running cost. Here is how they differ from a single-parent captive, and what they can and can’t cover.

≈ 75%
of the captives Marsh manages are single-parent1
$500,000
Vermont minimum capital for an association captive2
$1,000,000
Vermont minimum capital for a risk retention group2
Liability only
risk retention groups write liability cover, excluding workers’ compensation4

Three ways to share

1 of 3

Group captive

Several businesses own one captive together and share its results. Because a pool’s range of probable losses is narrower, group captives need less combined surplus than single-parent captives3.

Members share losses and must disclose a substantial amount of financial information3.

2 of 3

Association captive

A captive owned through a trade or professional association, insuring its members. Vermont sets its minimum capital at $500,0002.

3 of 3

Risk retention group

Authorised by the federal Liability Risk Retention Act of 1986 to provide liability insurance, specifically excluding workers’ compensation, to members with similar liability exposures4. Vermont’s minimum capital is $1,000,0002.

It must have at least two policyholders and does not need a fronting insurer4.

Single parent or shared?

A single-parent captive keeps your own record and your own results. A shared vehicle can make a captive viable at a smaller premium4, but your costs then depend partly on the other members’ losses, and a group captive often runs a higher expense ratio than a single-parent one4. The right choice turns on your premium, your record against the group’s, and how much control you want.

Start with your own numbers

Realtech’s captive design tool models a single-parent captive on your data and compares it with guaranteed cost, a retro and a large deductible. If the answer is “not yet” on your own, that is a reason to look at a shared vehicle.

Sources

Figures are published rules, estimates and benchmarks, not quotes. They vary by state, domicile, line of cover and year.

  1. Captive.com, “Marsh 2026 Benchmarking Report Highlights Continued Captive Growth” (1 June 2026): single-parent captives about 75% of Marsh-managed vehicles. captive.com Captive manager’s own book, as reported.
  2. Vermont Statutes, 8 V.S.A. § 6004, minimum capital by captive type. legislature.vermont.gov Statute.
  3. Captive.com (IRMI), “What Are Association and Group Captives?”: narrower range of probable losses, so lower combined surplus; shared losses; financial disclosure by members. captive.com Industry reference.
  4. A. M. Conway (Tillinghast–Towers Perrin), “Ratemaking for Captives and Alternative Market Vehicles,” Casualty Actuarial Society Forum, Winter 2005: risk retention groups; group captive expense ratios. casact.org Actuarial literature, dated.

This guide is general information about captive insurance. It is not insurance, legal or tax advice. Realtech is an independent consultancy and does not sell insurance.