IFRS 2 Part 4: Valuation — Option-Pricing Models and a Live Black-Scholes Calculator
Part 4 of a 7-part series on IFRS 2: Black-Scholes and binomial option-pricing models, the six key valuation inputs, and an interactive calculator to price your own option grant.
Quick Summary
- Grant-date fair value is the anchor for every equity-settled award, and getting it right means choosing the right pricing model for the instrument and, where relevant, the right treatment of market versus non-market conditions.
- Black-Scholes and the binomial (lattice) model are both acceptable for plain share options; a binomial model is preferred when the option has features Black-Scholes cannot capture, such as an expected early-exercise pattern.
- Six inputs drive every option-pricing model: share price, exercise price, expected volatility, expected life, risk-free rate, and expected dividends — and IFRS 2 has specific guidance on estimating each one for employee awards.
- Market conditions are priced in, not estimated separately — typically via a Monte Carlo simulation layered on top of the base option-pricing model.
- Use the calculator below to price a share option under Black-Scholes with your own assumptions.
SHARE-BASED PAYMENT — 7 GUIDES
Two Acceptable Families of Option-Pricing Model
IFRS 2 does not prescribe a single valuation model. It requires that the fair value of equity instruments granted be estimated using an option-pricing model that takes into account, at a minimum, the six factors listed above, and it explicitly recognizes two broad families as acceptable in practice.
Closed-Form Models: Black-Scholes-Merton
The Black-Scholes-Merton model produces a single fair-value figure directly from its six inputs, using a closed-form equation. It is the most widely used model for plain-vanilla share options because it is transparent, auditable, and inexpensive to apply — but it assumes European-style exercise (only at expiry) and cannot natively reflect an expectation that employees will exercise early, in tranches, or in response to specific triggers.
The Black-Scholes-Merton Formula (with a continuous dividend yield)
d₁ = [ln(S/K) + (r − q + σ²/2) × T] / (σ × √T)
d₂ = d₁ − σ × √T
Call Fair Value = S × e−qT × N(d₁) − K × e−rT × N(d₂)
Where S is the current share price, K is the exercise price, r is the risk-free rate, q is the expected dividend yield, σ is expected volatility, T is expected life in years, and N(·) is the cumulative standard normal distribution function.
Lattice (Binomial) Models
A binomial or lattice model breaks the option’s life into discrete time steps and, at each step, allows the share price to move up or down by a calibrated factor, building a tree of possible future share prices. Working backward from expiry, the model computes an expected, discounted payoff at each node. Because it is built step by step, a lattice model can incorporate features Black-Scholes cannot: expected early exercise, exercise multiples tied to how far the share price is above the exercise price, and even variable exercise behavior across different groups of employees.
Which one should you use? IFRS 2 does not mandate one model over the other. In practice, entities use Black-Scholes for simpler awards where early-exercise behavior is not expected to materially affect value, and move to a binomial (or more elaborate) model when employees are known to exercise well before contractual expiry — a very common real-world pattern for employee stock options, since employees often exercise as soon as they are vested and in-the-money rather than holding to maturity like a market participant would.
The Six Inputs, and How IFRS 2 Expects You to Estimate Them for Employee Awards
| Input | What It Means | Estimation Guidance |
|---|---|---|
| Share price | Current market price at grant date | Quoted price for listed entities; a recent independent valuation for unlisted entities |
| Exercise price | Price the holder pays to exercise | Fixed by the award’s terms; adjust for any indexed or variable strike features |
| Expected volatility | Expected variability of the share price over the option’s life | Historical volatility over a period matching expected life is the usual starting point; implied volatility from traded options is used where available; unlisted entities may reference a comparable listed peer group |
| Expected life | Expected period until exercise, not the full contractual term | Based on historical exercise patterns; must be shorter than the contractual term whenever early exercise is expected, since using the full term overstates fair value |
| Risk-free rate | Return on a risk-free instrument | Yield on a zero-coupon government bond with a maturity matching the option’s expected life |
| Expected dividends | Dividends the option holder will not receive during the option’s life | Based on current dividend policy and history; higher expected dividends reduce option fair value, since the holder forgoes them until exercise |
Live Calculator: Black-Scholes Option Fair Value
Enter your own assumptions below to compute the grant-date fair value of a share option under the Black-Scholes-Merton model. This mirrors the mechanics behind the Option Valuation tab of the downloadable Excel toolkit in Part 7, where the same inputs are also cross-checked against a 20-step binomial lattice.
For illustration only — always corroborate with an independent valuation for financial-reporting purposes, and use a binomial or Monte Carlo model where early exercise or market conditions apply.
Market Conditions: Layering a Monte Carlo Simulation
As Part 3 explained, a market condition (such as a TSR hurdle) must be built directly into grant-date fair value rather than treated as a separate probability estimate. Neither Black-Scholes nor a simple binomial lattice can price a TSR-relative payoff on its own, because the payoff depends on the joint behavior of the entity’s share price and a comparator index or peer group, not on the entity’s share price alone. In practice, this is handled with a Monte Carlo simulation: thousands of correlated share-price paths are simulated for the entity and its comparators, the plan’s vesting rule is applied to each simulated path to determine the payoff, and the fair value is the discounted average payoff across all simulated paths.
Honest limitation: a Monte Carlo simulation cannot be meaningfully reproduced in static spreadsheet formulas — it requires thousands of randomized, correlated price-path iterations, which is why the downloadable Excel toolkit in Part 7 provides full Black-Scholes and binomial-lattice valuation (for options without market conditions) but does not attempt to fake a Monte Carlo engine. Where an award includes a market condition, use dedicated valuation software or an external specialist.
What About Restricted Shares (No Exercise Price)?
A straightforward award of restricted shares — as opposed to options — has no exercise price and no optionality, so no option-pricing model is required at all. Fair value is simply the market price of the share at grant date, adjusted for any restrictions that will continue after vesting that a market participant would price into the transaction (for example, a post-vesting sale restriction), and adjusted to exclude the value of any dividends the holder will not be entitled to receive during the vesting period. The Share Valuation tab of the downloadable Excel toolkit in Part 7 builds this calculation out in full.
When Fair Value Cannot Be Estimated Reliably
In the rare cases where an entity concludes it cannot reliably estimate the fair value of equity instruments at grant date — most plausible for unlisted or newly listed entities lacking the historical data volatility estimation requires — IFRS 2 permits a fallback to intrinsic value, remeasured at each reporting date and at final settlement, with any change recognized in profit or loss. This is treated as a measurement of last resort, not a policy choice available whenever fair value estimation is merely inconvenient.
Need Help With Share-Based Payment Accounting?
From designing an equity incentive plan through valuing options and preparing the disclosures, our team can help you apply IFRS 2 correctly. Contact our Financial Advisory team today.