Kansas City Royals vs Seattle Mariners · All-Time
45 meetings tracked · closing-line graded
RECORD
17-28
MEETINGS
45
ATS
19-13
O / U
20-12
Key Insights
- ▸Seattle Mariners lead 28-17 across 45 tracked meetings.
- ▸Games have averaged 10.0 combined points.
- ▸Kansas City Royals have been the better ATS side (19-13).
- ▸Strong Over trend: 20-12 O/U.
Year-by-Year Record
| Season | Games | Kansas City Royals | Seattle Mariners | ATS | O / U | Avg Total |
|---|---|---|---|---|---|---|
| 2026 | 6 | 5 | 1 | 5-1 | 2-4 | 7.3 |
| 2025 | 7 | 3 | 4 | 4-3 | 4-3 | 8.3 |
| 2024 | 6 | 3 | 3 | 3-3 | 4-2 | 10.3 |
| 2023 | 7 | 1 | 6 | 3-4 | 6-1 | 12.3 |
| 2022 | 6 | 2 | 4 | 4-2 | 4-2 | 12.7 |
| 2019 | 7 | 2 | 5 | — | — | 11.4 |
| 2018 | 6 | 1 | 5 | — | — | 7.2 |
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Frequently Asked Questions
What is the Kansas City Royals vs Seattle Mariners record all-time?▾
Across 45 all-time meetings, the Seattle Mariners lead the series 28-17.
What is the ATS trend in Kansas City Royals vs Seattle Mariners games?▾
ATS: Kansas City Royals are 19-13 vs the spread in these matchups. Seattle Mariners are 13-19.
Do Kansas City Royals vs Seattle Mariners games go over or under?▾
Over/under: games between Kansas City Royals and Seattle Mariners have gone over 20 times and under 12 times, with an average combined score of 10.0.
When did Kansas City Royals and Seattle Mariners last play?▾
See Last Meetings section for detailed score, spread, and total data from the most recent Kansas City Royals vs Seattle Mariners games.
Where can I see the 5-year Kansas City Royals vs Seattle Mariners history?▾
A 5-year head-to-head page tracks every Kansas City Royals vs Seattle Mariners meeting from the last five full seasons. Link at the bottom of this page.
Data coverage: Trendline's head-to-head records include closing-line-graded games from 2018–2026. Older meetings aren't in this dataset yet.