X0609 4 2026-04-06 0 0001990354 Waystar Holding Corp. WAY 0001735839 PACKER GREGORY R false 1550 DIGITAL DRIVE, #300 LEHI UT 84043 0 1 0 0 Chief Legal officer 0 Common Stock 2026-04-06 4 F 0 4016 23.69 D 192948 D Common Stock 2026-08-01 4 A 0 232061 0 A 425009 D Includes unvested RSUs. The transaction represents shares of common stock withheld to pay taxes upon vesting of restricted stock units granted to the Reporting Person on April 1, 2025. The number of shares withheld was determined based on the actual sale price of shares sold on April 7, 2026 pursuant to a sell-to-cover transaction. Reflects a grant of restricted stock units ("RSUs") which vest over 2 years, with 12.5% vesting each quarter during year 1 and 50% vesting in year 2. Each RSU represents a contingent right to receive one share of common stock, $0.01 par value per share (the "Common Stock") upon settlement. /s/ Gregory R Packer 2026-08-03