Concept · C:pension-interest-cost

Pension interest cost

Working definition

The increase in the benefit obligation attributable to the passage of time, computed from the supplied opening obligation and discount-rate convention.

On this page
  1. Apply it
  2. Common mistake
  3. Keep the boundary clear
  4. Authority

Pension interest cost has one role in the employer's benefit accounting. Interest cost reflects passage of time on the discounted PBO under the supported rate and timing convention. It increases the obligation and enters periodic pension cost.

Apply it

With an $18 million opening PBO and a supported five-percent opening-balance convention, interest cost is $900,000. The multiplication checks the report without proving the selected rate.

Common mistake

Do not assume that interest cost is interest paid to retirees or lenders. Interest cost is the period increase in the measured obligation caused by the passage of time. That error would misclassify the unwinding of a discounted obligation as an external financing payment.

Keep the boundary clear

An interim remeasurement or weighted cash-flow convention may change the base. Accounting must not default to opening PBO when the actuarial schedule uses another supported method.

Authority

Read ASC 715-30-35-8 for interest on the projected benefit obligation.

Learning objectives

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Learning level

Apply this concept

  • Explain and apply pension interest cost within a reconciled employer benefit-plan workpaper using supplied authoritative and actuarial facts.

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Updated Sep 11, 2026 Review due Dec 11, 2026