# MLS county map: history and methodology

Research checked September 11, 2026. The executable dataset is `lib/data/mls-history.ts`; logo asset provenance is maintained separately in `public/data/mls-logo-sources.json`.

## What a season means

The map includes clubs that competed in the selected MLS regular season, from 1996 through 2026. It does not show their earlier NASL, USL or other league incarnations. Founding/announcement dates are not treated as MLS debut dates. Canadian MLS clubs participate in the distance calculation even though the counties shown are in the United States.

Each club uses an approximate central point in its regular home **municipality**, not an exact stadium coordinate, a market boundary, fan survey, driving route or population-weighted location. The reference points in the dataset are manually selected, rounded geographic coordinates for the named municipalities. They are cartographic approximations, not independently surveyed points. Results near a boundary can change under a stadium-based method. The county geometry and representative point method are documented in the geography source file.

For a permanent move during a season, the snapshot uses the home municipality in use at the end of the regular season. Examples are FC Dallas in Frisco in 2005, Real Salt Lake in Sandy in 2008, and Chicago back in Chicago in 2003. It includes season-long alternate homes such as Dallas in Southlake in 2003 and Chicago in Naperville in 2002. It excludes individual alternate games, cup-only venues, and temporary COVID-era relocations. NYCFC uses New York City for its home stadiums in the Bronx and Queens, excluding individual Harrison fixtures.

LA Galaxy and Chivas USA both use the same Carson point in 2005–2014. They genuinely tie under this method; any shared territory must retain both clubs, rather than inventing separate coordinates. LAFC uses Los Angeles from its separate 2018 debut.

Colors are editorial map fills drawn from the clubs' era palettes and adjusted for legibility. They are not a specification of official Pantone colors, nor a claim that every season's home jersey had that exact color. The identities follow the playing seasons associated with major primary crests. Anniversary marks, monochrome variants, jersey sponsors, championship stars, and every small production revision are outside this first edition.

The MLS display selects solid fills for each season using the atlas's neighboring-region IDs. It prefers the existing primary colors, then era-specific secondary and accent colors in `lib/data/mls-map-palettes.ts`, with lighter or darker shades when needed. Nonblack alternatives are preferred before introducing a black fill. Orlando retains its original purple and Atlanta its original red. `lib/club-history-colors.ts` checks every final adjacent pair of single-club territories, including borders whose original colors did not clash. Similar hues need a larger difference in shade; clearly different chromatic hues can remain closer in lightness. These editorial checks improve separation; they are not a guarantee for every form of color vision. Selection is deterministic for the same season and dataset, and it does not change source colors, club identities or nearest-club assignments. The legend and downloaded map use the same selected fills. Multi-color stripes remain reserved for equally close clubs sharing an anchor.

For 2026, club membership and home municipalities reflect information available on the research date, not a claim that the season has finished.

## Membership and counts

| Seasons | Clubs |
| --- | ---: |
| 1996–1997 | 10 |
| 1998–2001 | 12 |
| 2002–2004 | 10 |
| 2005–2006 | 12 |
| 2007 | 13 |
| 2008 | 14 |
| 2009 | 15 |
| 2010 | 16 |
| 2011 | 18 |
| 2012–2014 | 19 |
| 2015–2016 | 20 |
| 2017 | 22 |
| 2018 | 23 |
| 2019 | 24 |
| 2020 | 26 |
| 2021 | 27 |
| 2022 | 28 |
| 2023–2024 | 29 |
| 2025–2026 | 30 |

The file contains 33 historical club identities at franchise level: the 30 current clubs plus Tampa Bay Mutiny, Miami Fusion and Chivas USA. San Jose is one club with two active ranges, 1996–2005 and 2008–2026. Houston is separate and starts in 2006.

Primary sources for membership:

- [MLS original teams and early expansion timeline](https://www.mlssoccer.com/news/expansion-timeline-minnesota-united-becomes-mls-newest-expansion-team): the original ten and successive debut seasons through the mid-2010s.
- [MLS expansion retrospective](https://www.mlssoccer.com/news/look-back-history-mls-expansion): Chicago and Miami in 1998; Real Salt Lake and Chivas USA in 2005; Toronto in 2007; San Jose's return in 2008; Seattle in 2009; Philadelphia in 2010; Portland and Vancouver in 2011; Montreal in 2012; NYCFC and Orlando in 2015; Atlanta and Minnesota in 2017.
- [MLS on the 2002 contraction](https://www.mlssoccer.com/news/throw-did-eliminating-tampa-miami-save-mls): Tampa Bay and Miami cease to participate after the 2001 season. They are absent beginning in 2002.
- [MLS on Houston's name and origin](https://www.mlssoccer.com/news/how-houston-dynamo-got-their-name): players and staff move from San Jose for 2006, while the Earthquakes name, colors, logo and history remain in the Bay Area for the returning team. Houston 1836 was a preseason name and never played an MLS season under it.
- [Official Chivas USA closure announcement](https://www.chicagofirefc.com/news/mls-announces-new-conference-realignment-chivas-usa-cease-operations): closure on October 27, 2014, after its final season. The announcement's planned 2017 Los Angeles debut was superseded; LAFC actually entered in 2018, as shown by [MLS's review of LAFC's first regular season](https://www.mlssoccer.com/news/lafc-secure-best-regular-season-points-total-ever-mls-expansion-team).
- [Cincinnati's official award announcement](https://www.mlssoccer.com/news/major-league-soccer-awards-expansion-team-cincinnati): 2019 MLS debut.
- [MLS 2020 alignment announcement](https://www.mlssoccer.com/news/mls-2020-conference-alignment-inter-miami-east-nashville-west): Inter Miami and Nashville join for a total of 26.
- [Austin's official MLS debut announcement](https://www.mlssoccer.com/news/austin-fc-begin-mls-play-2021-leagues-27th-club): 27th club in 2021. Austin is not modeled as Columbus relocating.
- [Charlotte's inaugural kit announcement](https://www.mlssoccer.com/news/charlotte-fc-reveal-inaugural-carolina-kit-primary-jersey): 28th club, debuting in 2022.
- [MLS's St. Louis debut-season preview](https://www.mlssoccer.com/news/st-louis-city-sc-on-the-right-track-with-laying-preseason-foundation): 29th club in 2023.
- [San Diego's official expansion announcement](https://www.mlssoccer.com/news/major-league-soccer-awards-expansion-team-to-san-diego): 30th club, beginning play in 2025.
- [MLS's 2026 league overview](https://www.mlssoccer.com/news/about-major-league-soccer-x4174): 30 clubs in 2026.

## Identity changes

Names are season-facing display names, with abbreviated labels also provided. The short-lived Columbus SC name in May 2021 is not a separate season; the 2021 snapshot uses Columbus Crew after its restoration. San Jose's October 1999 announcement applies to the 2000 playing season. Offseason announcements are assigned to the next playing season; the Galaxy's July 2007 identity is used for 2007.

| Club | Season changes represented | Evidence |
| --- | --- | --- |
| Kansas City | Wiz 1996; Wizards 1997; Sporting Kansas City 2011 | [Club history](https://www.sportingkc.com/club/history/), [club brand history](https://www.sportingkc.com/news/sporting-kansas-city-brand-history) |
| San Jose | Clash through 1999; Earthquakes from 2000; returning crest from 2008; current design from 2014 | [MLS naming history](https://www.mlssoccer.com/news/how-san-jose-earthquakes-got-their-name), [MLS rebrand review](https://www.mlssoccer.com/news/mls-club-rebrands-recent-history-teams-changed-their-identities) |
| Dallas | Burn through 2004; FC Dallas from 2005 | [Official FC Dallas fact sheet](https://www.mlssoccer.com/news/fc-dallas-fact-sheet) explicitly keeps Burn through the remainder of 2004 |
| Colorado | Early green; blue/black era from 2003; burgundy and sky blue from 2007 | [Contemporary MLS match notes](https://www.mlssoccer.com/news/crew-rapids-hope-start-streak) confirm the 2003 color switch; [club's 2007 identity announcement](https://www.coloradorapids.com/news/colorado-rapids-unveil-new-team-identity); map fills are palette approximations |
| LA Galaxy | Swirl crest through 2006; shield and navy/white/gold era from 2007 | [Official Galaxy guide](https://www.lagalaxy.com/news/new-fan-guide-galaxy-101) |
| D.C. United | Original eagle 1996–1997; revised 1998–2015; redesigned from 2016 | [Club's original-logo retrospective](https://www.dcunited.com/news/tbt-original-logo), [MLS rebrand review](https://www.mlssoccer.com/news/mls-club-rebrands-recent-history-teams-changed-their-identities) |
| Columbus | Original Crew through 2014; Crew SC 2015–2020; Crew from 2021 | [2015 identity announcement](https://www.mlssoccer.com/news/columbus-crew-unveil-new-logo-brand-identity-nods-teams-heritage-city-supporters), [2021 restored name and revised crest](https://www.mlssoccer.com/news/columbus-crew-reveal-updated-crest-following-decision-to-retain-crew-name) |
| Chicago | Original through 2019; Fire FC/Crown in 2020–2021; new crest from 2022; red home palette returns 2024 | [2020 identity](https://www.chicagofirefc.com/news/chicago-fire-reveals-new-primary-badge-and-brand-identity-ahead-move-soldier-fie), [2022 crest schedule](https://www.chicagofirefc.com/news/chicago-fire-fc-unveils-new-crest-and-visual-identity-directly-inspired-more-200) |
| Houston | Dynamo through 2020; Dynamo FC and hexagonal crest from 2021 | [Club announcement](https://www.houstondynamofc.com/news/houston-dynamo-football-club-and-houston-dash-unveil-new-club-initiatives-brand) |
| New England | Original flag through 2021; circular R crest from 2022 | [MLS announcement](https://www.mlssoccer.com/news/new-england-revolution-unveil-new-crest) |
| Montreal | Impact through 2020; CF Montréal/snowflake in 2021–2022; revised crest from 2023 | [2021 identity and jersey](https://www.mlssoccer.com/news/cf-montreal-launch-new-primary-jersey-part-identity-change), [2023 logo announcement](https://www.mlssoccer.com/news/cf-montreal-unveil-new-logo) |
| Seattle | Original MLS crest 2009–2023; revised identity from 2024 | [MLS's 2024 brand announcement](https://www.mlssoccer.com/news/seattle-sounders-unveil-brand-evolution-before-50th-anniversary-in-2024) explicitly retains old marks through the 2023 playing season |
| New York City | Original badge through 2025; updated badge on kits from 2026 | [Club's updated badge announcement](https://www.newyorkcityfc.com/news/new-york-city-fc-unveil-updated-club-badge) announced the design in September 2024, with broader brand rollout in 2025; [kit specialist's launch report](https://www.footyheadlines.com/2024/09/new-york-city-2025-home-kit.html) distinguishes delayed 2026 jersey use. This map follows playing-kit adoption for this staged change. |
| New York / New Jersey | NY/NJ MetroStars, then MetroStars, then New York Red Bulls from 2006; Red Bull New York as the league's display name for 2026 | [2006 MLS purchase announcement](https://www.mlssoccer.com/news/red-bull-purchases-metrostars-invests-soccer-specific-stadium), [official 2026 club listing](https://www.mlssoccer.com/clubs/red-bull-new-york/), [December 2025 coach appointment for 2026](https://www.mlssoccer.com/news/red-bull-new-york-name-michael-bradley-head-coach). Red Bull New York was already the organizational name in 2006; 2026 represents a change in the league's usual display usage, not a new franchise. |
| Portland / Philadelphia | Portland's text-free primary from 2016 and white-axe revision from 2019; Philadelphia crest refinement from 2018 | [MLS rebrand review](https://www.mlssoccer.com/news/mls-club-rebrands-recent-history-teams-changed-their-identities) notes the 2016 and 2018 changes; [SportsLogos.net's 2019 crest entry](https://www.sportslogos.net/logos/view/283668012019/Portland-Timbers-Logo/2019/Primary-Logo) and [contemporary 2019 kit review](https://news.sportslogos.net/2019/02/28/mls-a-look-at-all-the-new-mls-uniforms-for-2019/soccer/) document the returning white axe |
| Real Salt Lake | Early wordmark crest through 2009; shield from 2010 | [SportsLogos.net primary crest archive](https://www.sportslogos.net/logos/view/39489852010/Real-Salt-Lake-Logo/2010/Primary-Logo). The first edition groups small 2005/2006 variants under the early mark. |
| Tampa Bay | First crest 1996–1999; revised blues 2000–2001 | [SportsLogos.net Mutiny timeline](https://www.sportslogos.net/logos/list_by_team/334/Tampa-Bay-Mutiny-Logos/) |

Minor historic crest variants and exact image sources are listed in the logo provenance file. Some archives index a logo by announcement year, while this dataset indexes the MLS season in which it is used. The MetroStars shield is labeled 2002 in several archives but was introduced for the 2003 playing season, so it begins in 2003 here. [3rd Degree's logo history](https://3rddegree.net/fc-dallas-history/all-time-mls-franchise-logos) documents that season distinction, the 1998 MetroStars name simplification, Colorado's 2001 primary-logo switch, Kansas City's 2007 mark, and the Red Bulls' 2008 removal of motion lines. Its unrelated expansion dates contain errors, so membership instead follows the primary MLS sources above. Where a variant could not be recovered, provenance must identify the fallback instead of implying an exact reproduction.

## Changes in regular home municipality

The municipality is derived from the regular home venue; the coordinates themselves remain approximate city reference points.

| Club | Municipality snapshots | Primary evidence |
| --- | --- | --- |
| LA Galaxy | Pasadena 1996–2002; Carson from 2003 | [Galaxy's official guide](https://www.lagalaxy.com/news/new-fan-guide-galaxy-101) |
| Dallas | Dallas 1996–2002; Southlake 2003; Dallas 2004; Frisco from 2005 | [Club 2024 media guide, history and transactions](https://images.mlssoccer.com/image/upload/v1710875874/assets/dal/2024_Media_Guide_wfb2m3.pdf), [2005 MLS schedule notes](https://www.mlssoccer.com/news/mls-releases-2005-schedule) |
| Colorado | Denver through 2006; Commerce City from 2007 | [2007 identity/stadium announcement](https://www.coloradorapids.com/news/colorado-rapids-unveil-new-team-identity), [MLS stadium opening timeline](https://www.mlssoccer.com/news/newly-approved-dc-united-stadium-next-long-line-soccer-specific-stadiums-mls) |
| Chicago | Chicago 1998–2001; Naperville 2002; Chicago 2003–2005; Bridgeview 2006–2019; Chicago from 2020 | [Club move explainer](https://www.chicagofirefc.com/news/keys-new-place-four-things-know-about-fires-move-soldier-field), [2024 record book](https://images.mlssoccer.com/image/upload/v1709589805/assets/chi/2024_Chicago_Fire_FC_Record_Book_FINAL_v2_1_ecubb3.pdf) records October 10, 2003 return and October 18 regular-season home finale at Soldier Field |
| San Jose | San Jose 1996–2005; Santa Clara 2008–2014; San Jose from 2015 | [Club's Buck Shaw retrospective](https://www.sjearthquakes.com/news/making-buck-shaw-pitch-perfect-story-behind-field-manager-kevin-moore), [club 2024 media guide](https://images.mlssoccer.com/image/upload/v1716340472/assets/sje/PDFs/2024%20Media%20Guide.pdf) |
| Real Salt Lake | Salt Lake City 2005–2007; Sandy from 2008 | [MLS stadium-opening preview](https://www.mlssoccer.com/news/weekly-update-era-begins) records the October 9, 2008 opener and last two regular-season home games in Sandy |
| Red Bulls / MetroStars | East Rutherford through 2009; Harrison from 2010 | [MLS history of the Harrison opening](https://www.mlssoccer.com/news/welcome-new-jersey-home-real-football-giants) |
| Kansas City | Kansas City, Missouri through 2007; Kansas City, Kansas from 2008 | [Official KCK home announcement](https://www.sportingkc.com/news/kck-home-2008-2009); CommunityAmerica Ballpark was the intermediate home before Sporting Park |
| Minnesota | Minneapolis 2017–2018; Saint Paul from 2019 | [Club's venue history](https://www.mnufc.com/news/50ktomidway-homes-minnesota-soccer), [Allianz Field opener](https://www.mnufc.com/news/loon-classics-mnufc-vs-new-york-city-fc-04132019) |
| Inter Miami | Fort Lauderdale 2020–2025; Miami from 2026 | [MLS report from the actual April 4, 2026 Nu Stadium opening](https://www.mlssoccer.com/news/nu-stadium-party-inter-miami-host-epic-home-opener) |

Other clubs retain a constant municipality in this simplified series. Philadelphia is represented by Chester, New England by Foxborough, Miami Fusion by Fort Lauderdale, and Chivas USA by Carson. Toronto, Vancouver and Montreal stay in their Canadian home municipalities during the pandemic seasons under the stated exception.

## Dataset validation

An independent expected-count sequence was checked against every one of the 31 season snapshots. All pass: `[10,10,12,12,12,12,10,10,10,12,12,13,14,15,16,18,19,19,19,20,20,22,23,24,26,27,28,29,29,30,30]` for 1996–2026. Every active season has exactly one applicable identity era and finite coordinates; every referenced logo key resolves to a local PNG asset. San Jose is absent in both 2006 and 2007. Unsupported or noninteger years return no clubs.