# Projected Benefit Obligation (PBO): What It Is, How It's Calculated, and What It Means for Investors Published: 2026-01-20 Author: Warren Team URL: https://www.heywarren.com/blog/projected-benefit-obligation --- Hidden inside the balance sheets of thousands of companies with defined benefit pension plans is a liability that dwarfs many of their other obligations, the projected benefit obligation. When pension funds are underfunded relative to their PBO, companies face mandatory cash contributions that can squeeze [free cash flow](/blog/cashflow-free) for years. For investors, analysts, and HR professionals, understanding what the projected benefit obligation is, how it changes, and what it signals about a company's financial health is essential knowledge that's often overlooked in favor of more headline-friendly metrics. This guide explains PBO from the ground up. ## What Is the Projected Benefit Obligation? The **projected benefit obligation (PBO)** is the present value of all future pension benefits that a defined benefit pension plan is expected to pay to current employees and retirees, based on service already rendered, assuming the plan continues and employees' salaries will increase until retirement. In simpler terms: the PBO is the actuarially estimated "IOU" the company owes its pension plan participants for the work they've already done. Three key aspects of this definition: ### 1. Present Value Future pension payments are worth less today than at the time of payment. The PBO discounts all future expected benefit payments back to today using a discount rate, typically the yield on high-quality corporate bonds (AA-rated) at the measurement date. A higher discount rate reduces PBO; a lower rate increases it. ### 2. All Future Benefits for Past and Current Service The PBO includes benefits earned not just this year, but for all prior years of service. It's the accumulated obligation for everything the employee has earned up to the measurement date, projected forward. ### 3. Assumes Future Salary Increases This is what distinguishes PBO from the **accumulated benefit obligation (ABO)**. The ABO uses current salary levels; the PBO projects what salaries will be at retirement and calculates benefits on those higher projected salaries. For most employees, PBO > ABO because benefits at retirement will be based on end-of-career (highest) salaries. **Example**: An employee now earns $60,000. Their defined benefit pension pays 1.5% × years of service × final average salary. The PBO for this employee would be calculated using the projected final salary at retirement (perhaps $120,000 at year 35), while the ABO would use the current $60,000 salary. ## PBO vs. ABO vs. VBO: The Three Obligation Measures | Measure | What It Assumes | When Used | |---------|----------------|-----------| | **VBO** (Vested Benefit Obligation) | Vested benefits at current salary | Minimum ERISA funding baseline | | **ABO** (Accumulated Benefit Obligation) | All earned benefits at current salary | Used in some [GAAP](https://www.fasb.org/) contexts; also called "funding liability" | | **PBO** (Projected Benefit Obligation) | All earned benefits at projected future salary | Required for balance sheet under ASC 715 (US GAAP) | ![VBO, ABO, and PBO differ by which salary assumption they use, with PBO required under US GAAP.](data:image/svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20viewBox%3D%220%200%20600%20211%22%20width%3D%22600%22%20height%3D%22211%22%20role%3D%22img%22%3E%3Ctitle%3EHierarchy%3C%2Ftitle%3E%3Crect%20width%3D%22100%25%22%20height%3D%22100%25%22%20fill%3D%22%23f8fafc%22%2F%3E%3Crect%20x%3D%22220%22%20y%3D%2220%22%20width%3D%22160%22%20height%3D%2258%22%20rx%3D%228%22%20fill%3D%22%232563eb%22%2F%3E%3Ctext%20x%3D%22300%22%20y%3D%2254%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22700%22%20fill%3D%22white%22%3EPension%20Obligation%3C%2Ftext%3E%3Cpath%20d%3D%22M%20300%2078%20L%20300%20105.5%20L%20120%20105.5%20L%20120%20133%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%222%22%20fill%3D%22none%22%2F%3E%3Crect%20x%3D%2240%22%20y%3D%22133%22%20width%3D%22160%22%20height%3D%2258%22%20rx%3D%228%22%20fill%3D%22white%22%20stroke%3D%22%230891b2%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22120%22%20y%3D%22158%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2213%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EVBO%3C%2Ftext%3E%3Ctext%20x%3D%22120%22%20y%3D%22176%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3EVested%2C%20current%20salary%3C%2Ftext%3E%3Cpath%20d%3D%22M%20300%2078%20L%20300%20105.5%20L%20300%20105.5%20L%20300%20133%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%222%22%20fill%3D%22none%22%2F%3E%3Crect%20x%3D%22220%22%20y%3D%22133%22%20width%3D%22160%22%20height%3D%2258%22%20rx%3D%228%22%20fill%3D%22white%22%20stroke%3D%22%230891b2%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22300%22%20y%3D%22158%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2213%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EABO%3C%2Ftext%3E%3Ctext%20x%3D%22300%22%20y%3D%22176%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3EAll%20earned%2C%20current%20salary%3C%2Ftext%3E%3Cpath%20d%3D%22M%20300%2078%20L%20300%20105.5%20L%20480%20105.5%20L%20480%20133%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%222%22%20fill%3D%22none%22%2F%3E%3Crect%20x%3D%22400%22%20y%3D%22133%22%20width%3D%22160%22%20height%3D%2258%22%20rx%3D%228%22%20fill%3D%22white%22%20stroke%3D%22%230891b2%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22480%22%20y%3D%22158%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2213%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EPBO%3C%2Ftext%3E%3Ctext%20x%3D%22480%22%20y%3D%22176%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3EAll%20earned%2C%20projected%20sal%E2%80%A6%3C%2Ftext%3E%3C%2Fsvg%3E) *VBO, ABO, and PBO differ by which salary assumption they use, with PBO required under US GAAP.* Under U.S. GAAP (ASC 715, formerly SFAS 87), companies must use the **PBO** as the primary pension obligation measure on the balance sheet. [International Financial Reporting Standards](https://www.ifrs.org/) (IAS 19) use a similar measure called the **defined benefit obligation (DBO)**. ## How PBO Is Calculated Actuaries calculate PBO using several key assumptions: ![PBO grows each year through service cost and interest cost, and shrinks when benefits are paid out.](data:image/svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20viewBox%3D%220%200%201090%20125%22%20width%3D%221090%22%20height%3D%22125%22%20role%3D%22img%22%3E%3Ctitle%3EFlow%20diagram%3C%2Ftitle%3E%3Crect%20width%3D%22100%25%22%20height%3D%22100%25%22%20fill%3D%22%23f8fafc%22%2F%3E%3Crect%20x%3D%2230%22%20y%3D%2225%22%20width%3D%22170%22%20height%3D%2275%22%20rx%3D%2210%22%20fill%3D%22white%22%20stroke%3D%22%232563eb%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22115%22%20y%3D%2267.5%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EPrior%20PBO%3C%2Ftext%3E%3Cline%20x1%3D%22205%22%20y1%3D%2262.5%22%20x2%3D%22237%22%20y2%3D%2262.5%22%20stroke%3D%22%2364748b%22%20stroke-width%3D%222%22%2F%3E%3Cpolygon%20points%3D%22244%2C62.5%20235%2C57.5%20235%2C67.5%22%20fill%3D%22%2364748b%22%2F%3E%3Crect%20x%3D%22245%22%20y%3D%2225%22%20width%3D%22170%22%20height%3D%2275%22%20rx%3D%2210%22%20fill%3D%22white%22%20stroke%3D%22%232563eb%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22330%22%20y%3D%2258.5%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EService%20Cost%3C%2Ftext%3E%3Ctext%20x%3D%22330%22%20y%3D%2278.5%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2211%22%20fill%3D%22%2364748b%22%3ENew%20benefits%20earned%3C%2Ftext%3E%3Cline%20x1%3D%22420%22%20y1%3D%2262.5%22%20x2%3D%22452%22%20y2%3D%2262.5%22%20stroke%3D%22%2364748b%22%20stroke-width%3D%222%22%2F%3E%3Cpolygon%20points%3D%22459%2C62.5%20450%2C57.5%20450%2C67.5%22%20fill%3D%22%2364748b%22%2F%3E%3Crect%20x%3D%22460%22%20y%3D%2225%22%20width%3D%22170%22%20height%3D%2275%22%20rx%3D%2210%22%20fill%3D%22white%22%20stroke%3D%22%232563eb%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22545%22%20y%3D%2258.5%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EInterest%20Cost%3C%2Ftext%3E%3Ctext%20x%3D%22545%22%20y%3D%2278.5%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2211%22%20fill%3D%22%2364748b%22%3EDiscount%20unwinding%3C%2Ftext%3E%3Cline%20x1%3D%22635%22%20y1%3D%2262.5%22%20x2%3D%22667%22%20y2%3D%2262.5%22%20stroke%3D%22%2364748b%22%20stroke-width%3D%222%22%2F%3E%3Cpolygon%20points%3D%22674%2C62.5%20665%2C57.5%20665%2C67.5%22%20fill%3D%22%2364748b%22%2F%3E%3Crect%20x%3D%22675%22%20y%3D%2225%22%20width%3D%22170%22%20height%3D%2275%22%20rx%3D%2210%22%20fill%3D%22white%22%20stroke%3D%22%232563eb%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22760%22%20y%3D%2267.5%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EActuarial%20Gains%2FLosses%3C%2Ftext%3E%3Cline%20x1%3D%22850%22%20y1%3D%2262.5%22%20x2%3D%22882%22%20y2%3D%2262.5%22%20stroke%3D%22%2364748b%22%20stroke-width%3D%222%22%2F%3E%3Cpolygon%20points%3D%22889%2C62.5%20880%2C57.5%20880%2C67.5%22%20fill%3D%22%2364748b%22%2F%3E%3Crect%20x%3D%22890%22%20y%3D%2225%22%20width%3D%22170%22%20height%3D%2275%22%20rx%3D%2210%22%20fill%3D%22white%22%20stroke%3D%22%232563eb%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22975%22%20y%3D%2258.5%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EUpdated%20PBO%3C%2Ftext%3E%3Ctext%20x%3D%22975%22%20y%3D%2278.5%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2211%22%20fill%3D%22%2364748b%22%3ELess%20benefits%20paid%3C%2Ftext%3E%3C%2Fsvg%3E) *PBO grows each year through service cost and interest cost, and shrinks when benefits are paid out.* ### Discount Rate The present value of future payments depends critically on the discount rate. Under U.S. GAAP: - Must reflect the rate at which pension benefits could be settled (effectively, high-quality corporate bond yields) - Typically uses a yield curve approach, matching the duration of expected benefit payments to corresponding bond yields - **Impact**: A 100 basis point (1%) increase in the discount rate typically reduces PBO by 10-20%, depending on plan demographics and duration This is why rising interest rates reduce pension liabilities, and falling rates dramatically increase them (as occurred after 2008 and again in 2020). ### Salary Growth Rate For final-pay plans, the assumed salary growth rate directly affects the projected benefit. Higher assumed salary growth increases PBO. ### Mortality Rates The PBO must account for how long participants are expected to live (and thus collect benefits). Updates to mortality tables (the U.S. uses Society of Actuaries mortality tables) can significantly affect PBO. ### Employee Turnover / Withdrawal Rates Not all employees stay through retirement. Higher assumed turnover reduces PBO. ### Expected Retirement Age Earlier assumed retirement increases PBO (more years of payments); later retirement decreases it. ### Service Cost: The Annual Addition to PBO Each year, two primary factors change the PBO: **Service cost**: The present value of the pension benefits earned by employees during the current year. This is the year's "accrual" of new benefits. **Interest cost**: The unwinding of the discount, the PBO grows each year because the payment date is one year closer. Interest cost = Beginning PBO × Discount Rate. **Actuarial gains and losses**: When actual experience or assumption changes differ from prior estimates. A decrease in the discount rate creates an actuarial loss (PBO increases); an increase creates an actuarial gain. **Benefits paid**: Actual pension payments to retirees reduce PBO. ## Pension Funded Status: PBO vs. Plan Assets The **funded status** of a pension plan = Fair Value of Plan Assets - PBO ![A $1.2B PBO against $900M in plan assets leaves a $300M pension liability on the balance sheet.](data:image/svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20viewBox%3D%220%200%20800%20210%22%20width%3D%22800%22%20height%3D%22210%22%20role%3D%22img%22%3E%3Ctitle%3EComparison%3C%2Ftitle%3E%3Crect%20width%3D%22100%25%22%20height%3D%22100%25%22%20fill%3D%22%23f8fafc%22%2F%3E%3Ctext%20x%3D%22230%22%20y%3D%2257.5%22%20text-anchor%3D%22end%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EPlan%20Assets%3C%2Ftext%3E%3Crect%20x%3D%22240%22%20y%3D%2225%22%20width%3D%22337.5%22%20height%3D%2255%22%20rx%3D%226%22%20fill%3D%22%232563eb%22%2F%3E%3Ctext%20x%3D%22589.5%22%20y%3D%2257.5%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22700%22%20fill%3D%22%232563eb%22%3E%24900%3C%2Ftext%3E%3Ctext%20x%3D%22230%22%20y%3D%22152.5%22%20text-anchor%3D%22end%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EPBO%3C%2Ftext%3E%3Crect%20x%3D%22240%22%20y%3D%22120%22%20width%3D%22450%22%20height%3D%2255%22%20rx%3D%226%22%20fill%3D%22%237c3aed%22%2F%3E%3Ctext%20x%3D%22702%22%20y%3D%22152.5%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22700%22%20fill%3D%22%237c3aed%22%3E%241.2K%3C%2Ftext%3E%3C%2Fsvg%3E) *A $1.2B PBO against $900M in plan assets leaves a $300M pension liability on the balance sheet.* **Overfunded**: Plan assets > PBO → The pension plan has more assets than needed to pay projected benefits. Reported as a non-current asset on the balance sheet. **Underfunded**: Plan assets < PBO → The pension plan has a shortfall. Reported as a non-current liability on the balance sheet, the "pension liability." **Example**: - PBO: $1.2 billion - Fair value of plan assets: $900 million - Funded status: -$300 million → **$300 million pension liability on balance sheet** This is the actual balance sheet entry required by ASC 715, the company must record the entire underfunded amount as a liability, replacing the pre-2006 approach that allowed off-balance-sheet smoothing. ### The Pension Liability's Impact on Financial Analysis When analyzing companies with significant pension plans: **Adjusted leverage**: Many analysts add the pension liability to long-term debt when calculating leverage ratios. A company that looks moderately leveraged may be significantly more leveraged once pension obligations are included. **Adjusted equity**: Underfunded pension plans reduce net equity. The pension deficit (after tax) flows through Other Comprehensive Income (OCI) to reduce retained earnings/equity. **Cash impact**: Underfunded plans require mandatory contributions under ERISA (for private plans) or government requirements. These contributions reduce [free cash flow](/blog/fcf-calculation) and limit financial flexibility. ## Reading Pension Disclosures: What to Look For Companies disclose detailed pension information in footnotes to their annual financial statements. Key items to analyze: ### Funded Status Trend Is the pension becoming more or less underfunded over time? Consistent deterioration signals growing risk. ### Key Actuarial Assumptions **Discount rate**: Is it consistent with market rates, or optimistically high (artificially reducing PBO)? Comparing to peers is important, higher discount rate assumptions vs. peers may be concealing a larger liability. **Expected long-term return on plan assets**: Companies use an assumed return to calculate pension expense. Higher assumed returns reduce pension expense in the income statement. Unrealistically high return assumptions (8-9% in a low-yield environment) understate pension expense. ### Sensitivity to Discount Rate Changes Most companies disclose how a 25-50 basis point change in discount rate affects PBO. This allows investors to assess how exposed the pension liability is to interest rate movements. ### Contributions Expected Companies typically disclose expected pension contributions for the next 12 months and beyond. Upcoming large required contributions can surprise investors unfamiliar with pension mechanics. ## PBO in Different Industries **Most exposed industries**: - **Airlines**: Legacy airlines have massive defined benefit pension obligations, one reason several (United, Delta, US Airways) used bankruptcy to restructure pension obligations - **Utilities**: Regulated utilities with large workforces and long operating histories - **Automakers**: GM's pension obligations were a significant driver of its 2009 bankruptcy - **Telecoms and industrials**: Long-established companies with decades of defined benefit accruals - **State and local governments**: Public pension funds use different accounting but face similar (often larger) funding challenges **Less exposed**: - Technology companies (typically use defined contribution 401(k) plans, not defined benefit) - Younger companies with shorter operating histories - Companies that have frozen or terminated their defined benefit plans ## Pension Obligation Reform: Freezing and Terminating Plans Many companies have responded to PBO risk by: **Freezing the plan**: No new benefits accrue after the freeze date. Existing accrued benefits remain; the PBO stops growing through service cost but continues to grow through interest cost and actuarial changes. **Terminating the plan**: The company purchases annuities from an insurance company to cover all accrued benefits (annuitization) or pays lump sums to participants. This eliminates the pension liability permanently but requires fully funding the plan first. **Shifting to defined contribution (DC)**: New hires receive 401(k) benefits rather than defined benefit, eliminating ongoing PBO growth for new participants. ## Conclusion The projected benefit obligation represents the present value of all future pension benefits earned through current service, assuming future salary increases. It's the most comprehensive and economically accurate measure of pension liability under U.S. GAAP, and for companies with large defined benefit plans, it can represent one of the most significant liabilities on the balance sheet. For investors, understanding PBO requires looking beyond earnings reports to pension footnote disclosures, examining funded status, actuarial assumptions, sensitivity analysis, and upcoming contribution requirements. Companies that appear financially strong can be harboring substantial pension-related financial risk that only becomes visible when you dig into the details. Ready to put this knowledge to work? Try Warren, your AI financial advisor, get personalized, conflict-free guidance at heywarren.com --- ## Related Reading **More from Warren**: - [Gold IRA: How Precious Metals IRAs Work, Rules, and Whether It's Worth It](/blog/gold-ira) - [EV/EBITDA: How to Use the Enterprise Value to EBITDA Multiple for Valuation](/blog/ebitda-to-ev) - [1035 Exchange: How to Swap Insurance or Annuity Contracts Without Triggering Taxes](/blog/1035-exchange) **Authoritative sources**: - [IRS, Retirement Plans](https://www.irs.gov/retirement-plans) - [Department of Labor, Retirement](https://www.dol.gov/general/topic/retirement) - [IRS Publication 590-A, Contributions to IRAs](https://www.irs.gov/pub/irs-pdf/p590a.pdf)