X0508 4 2025-01-10 0001743907 Sun Country Airlines Holdings, Inc. SNCY 0001850885 Mays Gregory A. C/O SUN COUNTRY AIRLINES HOLDINGS, INC. 2005 CARGO ROAD MINNEAPOLIS MN 55450 1 Chief Operating Officer & EVP 1 Common Stock, par value $0.01 per share 2025-01-10 4 M 0 164 5.30 A 66515 D Common Stock, par value $0.01 per share 2025-01-10 4 S 0 6147 16.0804 D 60368 D Employee Stock Option (Right to Buy) 5.30 2025-01-10 4 M 0 164 0 D 2029-07-01 Common Stock 164 403342 D This transaction was effected pursuant to a Rule 10b5-1 trading plan. The 10b5-1 trading plan was adopted on September 4, 2024. 5,983 of these shares sold represents the number of shares sold by the reporting person to cover tax withholding obligations in connection with the vesting of restricted stock units. The sale of these 5,983 shares 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. 164 of these shares were sold pursuant to a Rule 10b5-1 trading plan. The 10b5-1 trading plan was adopted on September 4, 2024. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $16.00 to $16.35, inclusive. The reporting person undertakes to provide to Sun Country Airlines Holdings, Inc. ("Sun Country"), any security holder of Sun Country, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote (3) to this Form 4. This transaction was effected pursuant to a Rule 10b5-1 trading plan. The 10b5-1 trading plan was adopted on September 4, 2024. Grants may have a graded vesting schedule. Date Exercisable will vary for each vesting tranche. /s/ Rose Neale, as attorney-in-fact for Gregory Mays 2025-01-14