A discount rate is the interest rate used to convert future dollars into their value today, and the phrase covers two different things depending on who’s using it. In finance, it’s the rate an investor or business applies to future cash flows to figure out what they’re worth right now, and it’s usually calculated as a company’s weighted average cost of capital. At the Federal Reserve, it’s the rate the central bank charges commercial banks that borrow directly from it, and it’s set administratively by the Fed’s Board of Governors. Both rest on the same idea: a dollar today is worth more than a dollar later. They just do very different jobs.
The Two Meanings, Kept Separate
The financial discount rate is a valuation tool. Investors, analysts, and corporate finance teams use it to decide whether a future payoff justifies today’s outlay. It’s an input you choose or calculate based on the risk and opportunity cost of the money involved.
The Federal Reserve’s discount rate is a monetary policy lever. It’s the rate charged when commercial banks borrow directly from a regional Federal Reserve Bank through the “discount window,” and as of early 2026, the primary credit rate at the window is 3.75%.1FRED | St. Louis Fed. Discount Window Primary Credit Rate (MPCREDIT) It sits alongside — but is distinct from — the more widely reported federal funds rate, whose target range is currently 3.50% to 3.75%.
Most people searching for how to calculate a discount rate want the financial version. That’s where the math lives.
What the Financial Discount Rate Compensates For
A discount rate has two jobs baked into a single number.
The first is paying you for waiting. If you don’t have your money now, you can’t invest it, so any future payment needs to clear the return you could have earned in the meantime. This baseline is usually pegged to the yield on U.S. Treasury bonds, the closest thing to a risk-free return. In early 2026, the 10-year Treasury yield sits around 4.2%.
The second is paying you for risk. A Treasury bond will almost certainly pay. A speculative startup might not pay at all. The riskier the future cash flow, the higher the discount rate an investor demands. That risk premium stacks on top of the risk-free rate and can range from a couple of percentage points for a stable, established business to double digits for ventures with uncertain outcomes.
Put together, the discount rate is your opportunity cost with teeth. If you can reliably earn 10% elsewhere, any new project needs to offer at least that much to justify pulling capital away.
How to Calculate a Discount Rate Using WACC
For most companies, the working discount rate is the Weighted Average Cost of Capital, or WACC. It blends the cost of every dollar the company raises — both debt and equity — in proportion to how much of each it uses.
The formula:
WACC = (E/V) × Re + (D/V) × Rd × (1 – t)
Where:
- E = market value of equity
- D = market value of debt
- V = E + D (total capital)
- Re = cost of equity
- Rd = cost of debt
- t = corporate tax rate
Any new project the company takes on must earn at least its WACC to cover the cost of the money used to fund it.
Cost of Debt
The cost of debt is the easier half. It’s the effective interest rate the company pays on its borrowings, adjusted for one important detail: interest is generally tax-deductible under 26 U.S.C. § 163, so the real after-tax cost is lower than the sticker rate.2Office of the Law Revision Counsel. 26 USC 163 – Interest With the federal corporate tax rate at 21%, a company paying 6% on its loans has an after-tax cost of debt of roughly 4.74% (6% × 0.79).
Cost of Equity
Cost of equity is harder because shareholders don’t get fixed payments. The standard approach is the Capital Asset Pricing Model:
Re = Rf + β × (Rm – Rf)
Where:
- Rf = risk-free rate, typically the 10-year Treasury yield
- β (beta) = how much the stock moves relative to the market
- (Rm – Rf) = equity risk premium, the extra return investors expect for holding stocks over Treasuries
A widely referenced estimate of the U.S. equity risk premium for 2026 is around 4.2%. Beta is where the calculation gets company-specific. A beta of 1.0 means the stock moves in step with the market. A utility might sit at 0.5, meaning it’s less volatile than the market and investors demand less return. An aggressive tech firm might carry a beta of 1.5 or higher, pushing its cost of equity up.
Plug the pieces into the WACC formula and you have a company-wide discount rate.
When WACC Doesn’t Fit
A single WACC works as a general benchmark, but it stops working when a company evaluates projects with very different risk profiles. A consumer goods firm looking at a cryptocurrency venture shouldn’t use the same discount rate it applies to a new packaging line. The fix is a project-specific risk premium layered on top of WACC. A company with an 8% WACC might apply a 12% rate to a speculative expansion.
Small, privately held businesses face a different obstacle: no publicly traded stock, no observable beta, no clean WACC. These firms typically use a build-up method, stacking components together: the risk-free rate, an equity risk premium, a size premium reflecting that smaller companies are riskier, and a company-specific risk premium. For the smallest closely held firms, size premiums alone can run well into double digits.
Putting the Rate to Work: Net Present Value
The most common use of a discount rate is calculating Net Present Value, the standard test for whether an investment is worth making. NPV takes every expected future cash flow, discounts each one back to today’s dollars, and subtracts the upfront cost. The result tells you, in today’s money, how much value the project creates.
NPV = Σ [Ct / (1 + r)^t] – C₀
Ct is the cash flow in each future period t, r is the discount rate, and C₀ is the initial investment. The exponent compounds the discount over time, so distant cash flows get penalized more heavily than near ones. A dollar arriving 20 years out is worth far less today than a dollar arriving next year.
A positive NPV means the project returns more than it costs after accounting for the time value of money. A negative NPV means it doesn’t clear the bar.
A Worked Example
Consider a $100,000 investment expected to generate $30,000 per year for five years. At a 10% discount rate, the present value of those cash flows totals about $113,700, producing an NPV of roughly $13,700. The project clears the hurdle.
Raise the discount rate to 15% and the present value drops to about $100,600. The NPV is barely positive. At 16%, NPV goes negative and the project should be rejected.
That’s how sensitive a valuation is to the rate you choose. The same cash flows can look like a solid win or a losing bet depending on a few percentage points.
Discounted Cash Flow Analysis
NPV is one flavor of discounted cash flow analysis, the standard method for valuing whole companies, real estate, and other income-producing assets. Analysts project free cash flows over five to ten years, discount them using WACC or the cost of equity, and add a terminal value for everything beyond the forecast horizon. The discount rate is the most influential input in the model. Small changes ripple through every projected year and amplify in the terminal value, which often accounts for more than half the total valuation.
The Federal Reserve’s Discount Rate
The Fed’s version of the discount rate is a completely different animal. It’s the interest rate charged when commercial banks borrow directly from a regional Federal Reserve Bank through the discount window, and it signals how tight or loose the Fed wants credit conditions to be.
The discount window operates on three tiers:
- Primary credit, for financially sound banks that need short-term backup funding. The rate is set relative to the federal funds target range and is designed to discourage routine borrowing.3The Federal Reserve. Primary and Secondary Credit Programs
- Secondary credit, for banks that don’t qualify for primary credit, usually because of financial weakness. The rate runs 50 basis points above the primary rate.3The Federal Reserve. Primary and Secondary Credit Programs
- Seasonal credit, for smaller banks with predictable annual swings in funding needs, such as agricultural lenders during planting season. The rate floats based on an average of the federal funds rate and three-month CD rates.4The Federal Reserve Discount Window. Seasonal Credit Program
The Fed doesn’t calculate this rate the way a business calculates WACC. It’s set by the Board of Governors as a policy decision. Every discount window loan must be fully backed by collateral, and eligibility is governed by Federal Reserve Regulation A.5eCFR. Part 201 Extensions of Credit by Federal Reserve Banks (Regulation A) The window functions as a lender of last resort, keeping temporary cash squeezes at solvent banks from spiraling into broader instability.
How the Two Rates Connect
The Fed’s rate decisions feed directly into every financial discount rate calculation. When the Federal Reserve raises its target federal funds rate, the risk-free rate — the foundation of CAPM and WACC — moves up. Cost of equity rises. Banks charge more on loans, so cost of debt rises too. WACC climbs across the economy.
Higher WACC means fewer projects clear the profitability hurdle. Companies shelve expansion plans. Consumers face pricier mortgages. That deliberate cooling is how the Fed fights inflation. Rate cuts run the process in reverse, lowering WACC, making marginal projects look profitable, and encouraging investment.
The effect is most dramatic for long-duration assets like growth stocks, real estate, and infrastructure. These get most of their value from cash flows far in the future, and distant cash flows are the most sensitive to changes in the discount rate. Shifting the rate from 7% to 9% cuts the present value of a cash flow arriving in 20 years by more than 25%. That’s why technology stocks can swing sharply on a change in the Fed’s tone about future policy. Investors aren’t reacting to today’s earnings; they’re repricing decades of expected future earnings through a different discount rate.