in-force business

At any given moment, some of an insurer's policies are live and protecting customers right now, while others have expired or not yet started. The in-force business is the set of policies that are currently active — coverage is on, the clock is running, and a loss today would be covered. It is the company's working portfolio at a snapshot in time, like counting how many cars are on the road right now rather than how many were sold all year.

In-force is a 'stock' measured at a date, not a 'flow' measured over a period — which is the key contrast with written premium. You might measure it as the count of active policies, the in-force premium (the annualized premium of all active policies), or the in-force exposure. A book that wrote 12,000 of premium over a year might have only, say, 6,000 of premium in force on 31 December, because some of that year's policies have already expired and renewals have not all happened. As policies are sold and renewed the in-force grows; as they expire or lapse it shrinks.

It matters as the live measure of how much risk the company is carrying right now, which feeds capital and catastrophe analysis: if a hurricane hits today, the in-force is what is exposed. It is also the base for retention and growth analysis — comparing in-force across dates shows whether the book is expanding or shrinking. A common confusion: in-force premium is an annualized snapshot, not the premium actually collected in a period, so it should not be plugged into a loss ratio in place of earned premium.