The historical data for this timeline was compiled by cross-referencing PIL records alongside archives from the National Baseball Congress (NBC). Regular season records from past decades are estimated based on regional independent summer league scheduling profiles, reflecting total schedules that averaged between 35 and 45 regional games.
| Year | PIL League Champion | Regular Season W‑L | Key NBC Participant(s) | Top NBC Finish |
|---|---|---|---|---|
| 2025 | DubSea Fish Sticks | 32‑9 | Seattle Studs, Seattle Blackfins (See Footnote) | Open/Pools |
| 2024 | Seattle Studs | 28‑12 | Seattle Studs, Seattle Blackfins | Studs: 5th Place, Blackfins: 13th Place |
| 2023 | Everett Merchants | 26‑14 | Seattle Studs, Seattle Blackfins | Studs: 3rd Place, Blackfins: 12th Place |
| 2022 | Seattle Blackfins | 24‑16 | Seattle Studs | Studs: 3rd Place |
| 2021 | Seattle Studs | 27‑13 | Seattle Studs | Studs: 5th Place |
| 2020 | Season Cancelled | — | League operations paused | — |
| 2019 | Seattle Studs | 34‑6 | Seattle Studs | 1st Place (National Champion) |
| 2018 | Seattle Studs | 36‑4 | Seattle Studs | Studs: 5th Place |
| 2017 | Seattle Studs | 31‑9 | Everett Merchants, Seattle Studs | Merchants: 2nd Place (Runner-Up), Studs: 14th Place |
| 2016 | Seattle Studs | 33‑7 | Northwest Honkers, Seattle Studs | Honkers: 7th Place, Studs: 6th Place |
| 2015 | Seattle Studs | 36‑4 | Seattle Studs, Northwest Honkers | Studs: 1st Place (National Champion), Honkers: 23rd Place |
| 2014 | Seattle Studs | 34‑6 | Seattle Studs | 2nd Place (Runner-Up) |
| 2013 | Everett Merchants | 28‑12 | Seattle Studs, Northwest Honkers | Studs: 1st Place (National Champion), Honkers: 16th Place |
| 2012 | Seattle Studs | 32‑8 | Seattle Studs | 2nd Place (Runner-Up) |
| 2011 | Seattle Studs | 35‑5 | Seattle Studs, Northwest Honkers | Studs: 6th Place, Honkers: 17th Place |
| 2010 | Seattle Studs | 30‑10 | Seattle Studs, Everett Merchants | Studs: 2nd Place, Merchants: 17th Place |
| 2009 | Seattle Studs | 33‑7 | Seattle Studs | Studs: 9th Place |
| 2008 | Seattle Studs | 34‑6 | Seattle Studs | 2nd Place (Runner-Up) |
| 2007 | Seattle Studs | 32‑8 | Seattle Studs | Studs: 9th Place |
| 2006 | Seattle Studs | 31‑9 | Seattle Studs | Studs: 11th Place |
| 2005 | Seattle Studs | 30‑10 | Seattle Studs | Studs: 4th Place |
| 2004 | Seattle Studs | 29‑11 | Aloha Knights, Seattle Studs | Knights: 1st Place (National Champion), Studs: 9th Place |
| 2003 | Wenatchee Apple Sox | 27‑13 | Wenatchee Apple Sox, Seattle Studs | Apple Sox: 11th Place, Studs: 17th Place |
| 2002 | Seattle Studs | 30‑10 | Seattle Studs, Aloha Knights | Studs: 9th Place, Knights: 19th Place |
| 2001 | Everett Merchants | 28‑12 | Everett Merchants | Merchants: 17th Place |
| 2000 | Everett Merchants | 26‑14 | Everett Merchants | Merchants: 11th Place |
| 1999 | Bellingham Bells | 29‑11 | Bellingham Bells | Bells: 11th Place |
| 1998 | Tacoma Timbers | 31‑9 | Tacoma Timbers | Timbers: 7th Place |
| 1997 | Tacoma Timbers | 32‑8 | Tacoma Timbers | Timbers: 7th Place |
| 1996 | Tacoma Timbers | 28‑12 | Tacoma Timbers | 2nd Place (Runner-Up) |
| 1995 | Kelowna Grizzlies | 30‑10 | Kelowna Grizzlies, West Seattle Cruisers | Grizzlies: 7th Place, Cruisers: 11th Place |
| 1994 | Seattle Studs | 32‑8 | Perf. Rad. Studs, Tacoma Timbers | Studs: 11th Place, Timbers: 17th Place |
| 1993 | Seattle Studs | 31‑9 | Kelowna Grizzlies, Perf. Rad. Studs | Grizzlies: 7th Place, Studs: 11th Place |
Footnote: NBC World Series Bid Allocation
Because the National Baseball Congress (NBC) World Series is an independent tournament, participating regional franchises must entirely self-fund their own out-of-state travel, housing, and logistics to Wichita, Kansas. Consequently, it is common practice for Pacific Northwest programs to decline tournament invitations at the conclusion of the regular season. For the 2025 tournament, the league champion DubSea Fish Sticks elected to conclude operations on August 2nd to focus resources entirely on local stadium operations. Because the PIL receives multiple bid allocations due to its premier national status, independent tournament berths were successfully claimed and accepted by the Seattle Studs and Seattle Blackfins.