X0407 4 2023-06-30 0001743907 Sun Country Airlines Holdings, Inc. SNCY 0001850489 Whitney Grant C/O SUN COUNTRY AIRLINES HOLDINGS, INC.C 2005 CARGO ROAD MINNEAPOLIS MN 55450 1 Chief Revenue Officer & SVP 0 Common Stock, par value $0.01 per share 2023-07-03 4 S 0 396 22.4305 D 15732 D Employee Stock Option (Right to Buy) 5.30 2023-06-30 4 A 0 90380 0 A 2023-06-30 2029-07-31 Common Stock 90380 229581 D Represents the number of shares sold by the reporting person to cover tax withholding obligations in connection with the vesting of restricted stock units. This sale is mandated to satisfy the tax withholding obligations which are funded by a "sell to cover" transaction and does not represent a discretionary trade by the reporting person. On July 31, 2019, the reporting person was granted an option to purchase 165,232 shares of common stock. Upon a change in control, the option vests 33% if the Company's private equity investors achieve a MOIC of at least 3.0x, and 100% if the Company's private equity investors achieve a MOIC of at least 5.0x, with vesting with respect to achievement in between 3.0x and 5.0x subject to linear interpolation. If a change in control has not occurred by certain measurement dates following the Company's initial public offering, the unvested portion of the option may be eligible to vest based on achievement of certain performance criteria. On June 16, 2023, a change in control occurred and vesting of the option as to 4,627 shares occurred on that date. On June 29, 2023, the Company's Compensation Committee determined pursuant to the award agreement that the performance criteria for the final installment were met, resulting in vesting as to an additional 90,380 shares on June 30, 2023. /s/ Rose Neale, as attorney-in-fact for Grant Whitney 2023-07-05