☰A single-parent captive has one owner and insures only that company. A group captive is owned by many unrelated members who share risk. The choice usually comes down to premium size and appetite for control.
A single-parent captive gives its owner full control over coverage design, claims decisions, and surplus, and it becomes economic when a company's insurable premium is large enough to carry the captive's own operating costs, often around $1 million and up. A group captive spreads those fixed costs across members, so businesses with smaller premiums can still keep underwriting profit, but each member accepts shared governance, shared risk with the other members, and the group's rules on collateral and loss control.
Many companies start in a group captive and graduate to a single-parent structure as premiums grow. The economics of both paths can be modeled before any commitment.