The Titans built an early lead, then clamped down on defense to remain undefeated.
Lexi Raymore hit two 3-pointers to help Union lead 20-12 after the first quarter. Union (6-0) extended that lead and entered the fourth quarter up 48-31.
Mason Oberg led the Titans with 11 points while Mackenzie Lewis added 10.
Snohomish, which finished fourth in the 3A state playoffs last year, fell to 1-4.
UNION 52, SNOHOMISH 43
SNOHOMISH — Cheyenne Rodgers 6, Kayla Soderstrom 8, Averie Allbaugh 0, Ella Gallatin 11, Gracie VanAssche 3, Sara Rodgers 4, Kaylin Beckman 7, Kali Cole 0. Totals 15 (5) 7-14 43.
UNION — Lexi Raymore 9, Mason Oberg 11, Lolo Weatherspoon 6, Sydney Cowling 0, Abbey Kaip 3, Kaneyl Carpenter 2, Caitlyn Leake 3, Mackenzie Lewis 10, Sarah Litchford 6, Ariel Ammentorp 2. Totals 0 (0) 0-0 00.
Snohomish 12 11 8 12–43
Union 20 15 13 4–52