Whole Life Reserve Calculator
The net premium reserve is the liability an insurer holds for a whole life policy at a given duration: the present value of future benefits minus the present value of future net premiums. The prospective formula per unit is tVx = A(x+t) - Px times a-double-dot(x+t). This calculator takes the whole life insurance value and annuity-due at the attained age, the level net premium per unit set at issue, and the face amount, then returns the reserve per unit and the dollar reserve. All actuarial inputs are user-editable so the page works for any mortality table and interest assumption.
Whole life reserve formula
PV future benefits per unit = A(x+t)
PV future net premiums per unit = Px * a-double-dot(x+t)
Reserve per unit tVx = A(x+t) - Px * a-double-dot(x+t)
Dollar reserve = face * tVx
The prospective reserve looks forward: it is the shortfall between what the insurer expects to pay and what it expects to collect, all at present value.
Reserve context
- The net premium reserve at issue is zero and rises with duration for whole life.
- The prospective and retrospective reserves are equal under the same basis.
- Px must be set from the same issue-age table used to value A and the annuity.
- Statutory reserves follow NAIC valuation rules and a prescribed mortality basis.
- Use a consistent mortality table and interest rate throughout.
Whole life reserve: frequently asked questions
What is a net premium reserve?
A net premium reserve is the liability an insurer holds for a policy at a given duration: the expected present value of future benefits minus the expected present value of future net premiums. For whole life it grows over time as the policy ages and the insurer accumulates funds to meet the rising cost of insurance.
How is the prospective reserve computed?
Per unit, tVx = A(x+t) - Px times a-double-dot(x+t), where A(x+t) is the whole life insurance present value at the attained age, a-double-dot(x+t) is the life annuity-due there, and Px is the level net premium per unit set at issue. Multiplying by the face amount scales it to the policy.
What is Px, the net premium per unit?
Px is the level annual net premium per unit of benefit, set at issue as Ax divided by a-double-dot x. You enter it directly here, so the page works for any policy regardless of the underlying table. You can compute Px with our net single premium and annuity-due tools.
Where do A(x+t) and a-double-dot(x+t) come from?
They are computed from a mortality table and interest rate at the attained age x+t. Use a Society of Actuaries valuation table or our commutation function tool. They are user-editable inputs because the right table depends on the insured population.
Should the reserve ever be negative?
A standard net premium reserve at issue is zero and rises thereafter, so it should not be negative for whole life. A negative result usually means the inputs are inconsistent, for example a Px that does not match the issue-age table used for A and the annuity.
Official sources
- Society of Actuaries: SOA reserves and life-contingencies materials.
- National Association of Insurance Commissioners: NAIC statutory valuation standards.
Reviewed by the CalculatorHub team, edited by James Graham, 17 June 2026. See our methodology.