9.Stock-based compensation

Stock-based compensation expense is measured on the grant date based on the fair value of the award. Stock-based compensation expense is recognized on a straight-line basis over the requisite service period for awards expected to vest. The estimated grant date fair value of stock options was determined using a Black-Scholes valuation model using the following weighted-average assumptions for the periods indicated:

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The expected volatility is based on the historical volatility of the Company’s common stock. The risk-free interest rate is based on the United States Treasury yield curve in effect on the date of grant for the respective expected life of the option. The expected life represents the time the options granted are expected to be outstanding. The expected life of options granted is derived from historical data on Ulta Beauty stock option exercises. Forfeitures of stock options are estimated at the grant date based on historical rates of stock option activity and reduce the stock-based compensation expense recognized. The Company does not currently pay a regular dividend.

The Company granted 41 and 48 stock options during the 13 weeks ended April 29, 2023 and April 30, 2022, respectively. Stock-based compensation expense for stock options was $1,470 and $2,342 for the 13 weeks ended April 29, 2023 and April 30, 2022, respectively. The weighted-average grant date fair value of these stock options was $200.67 and $149.14 for the 13 weeks ended April 29, 2023 and April 30, 2022, respectively. At April 29, 2023, there was approximately $16,402 of unrecognized stock-based compensation expense related to unvested stock options.

There were 38 and 50 restricted stock units issued during the 13 weeks ended April 29, 2023 and April 30, 2022, respectively. Stock-based compensation expense for restricted stock units was $4,359 and $4,452 for the 13 weeks ended April 29, 2023 and April 30, 2022, respectively. At April 29, 2023, there was approximately $39,616 of unrecognized stock-based compensation expense related to restricted stock units.

There were 32 and 37 performance-based restricted stock units issued during the 13 weeks ended April 29, 2023 and April 30, 2022, respectively. Stock-based compensation expense for performance-based restricted stock units was $3,892 and $3,562 for the 13 weeks ended April 29, 2023 and April 30, 2022, respectively. At April 29, 2023, there was

approximately $38,418 of unrecognized stock-based compensation expense related to performance-based restricted stock units.