Which U.S. cities have the strongest sanctuary policies and what exactly do those ordinances say?
Executive summary
Chicago, San Francisco, Los Angeles, and Seattle are repeatedly cited as among the U.S. cities with the strongest sanctuary policies, each backed by formal ordinances or longstanding municipal rules that limit local cooperation with federal immigration enforcement [1] [2] [3] [4]. Federal agencies and advocacy groups map and dispute the scope of those protections, and the Justice Department has published lists of jurisdictions it says materially impede federal enforcement [5] [6] [7].
1. The headline players: Chicago, San Francisco, Los Angeles, Seattle
Chicago’s Welcoming City ordinance—first adopted in 2006 and expanded in later years—has been a model for municipal sanctuary policy and was reported to have been strengthened in 2025 with expanded protections for minors and users of municipal services [4] [1]. San Francisco’s “Due Process for All” ordinance, passed in 2013 and reaffirmed with privacy expansions in 2025, explicitly restricts cooperation with ICE detainer requests and limits when law enforcement can inform federal officials about releases [2] [1]. Los Angeles, long operating with informal noncooperation, has moved toward formal ordinances protecting people from certain federal immigration actions, according to advocacy tallies and reporting [3]. Seattle maintains a prohibition on asking about immigration status dating to 2003 and passed a 2017 City Council ordinance that set high procedural bars for complying with ICE detainers or administrative warrants [4].
2. What these ordinances actually say in practice
Common language across the strongest ordinances includes prohibitions on using municipal funds or personnel to assist federal immigration enforcement, limits on honoring ICE detainer requests without a judicial warrant, restrictions on querying immigration status in routine services, and privacy protections for municipal IDs and records [2] [4] [1] [6]. San Francisco’s ordinance specifically forbids routine cooperation with ICE detainers and narrows information-sharing about release dates [2], while Chicago’s Welcoming City framework aims to prevent immigration status inquiries in city interactions and was reported to add protections for minors and service users in 2025 [4] [1]. Seattle’s 2017 language ties noncooperation to Fourth Amendment-style judicial-warrant standards for detainers and frames immigration-status questioning as a form of biased policing [4].
3. Mapping, disagreement and federal pushback
Multiple actors maintain lists and maps of sanctuary jurisdictions, but they disagree sharply on criteria and scale: the Center for Immigration Studies and FAIR characterize many jurisdictions as obstructing enforcement and publish extensive lists and maps [5] [8] [3], while the Justice Department compiled a designated list in 2025 under an executive order that it says reflects jurisdictions whose laws or policies impede federal enforcement [6] [7]. The DOJ’s public designation process and subsequent updates have prompted calls for methodological clarity from municipal associations and legal groups, underscoring that “sanctuary” status is as much political and administrative as legal [9].
4. Caveats, state-level variation and contested labels
“Sanctuary” is not uniform: some states (including California, Illinois, Minnesota and New York) are identified by federal reporting or press summaries as sanctuary states or jurisdictions with broad protections, but state and local rules differ in scope and enforcement mechanics [10] [1]. Cities like Denver provide a cautionary example: some reporting says Denver does not self-identify as a sanctuary city because it lacks a formal ordinance, even as local law-enforcement memos have instructed limited detainer cooperation in the past [11] [4]. Legal and political conflicts—state bans on sanctuary policies, municipal ordinances, and federal designation—mean the practical protections a resident encounters can vary sharply by agency, program, and courtroom outcome [12] [6].
5. Bottom line
The “strongest” sanctuary cities are those with formal, codified ordinances that restrict resource-sharing with ICE, refuse to honor administrative detainers without a warrant, prohibit routine immigration-status inquiries, and protect municipal records—San Francisco, Chicago, Los Angeles and Seattle are the most consistently cited examples in recent reporting—while federal lists and advocacy maps reveal contested definitions and ongoing legal friction [2] [4] [3] [6]. Where local language exists, its effect depends on implementation, intergovernmental pressure, and court challenges, so the map of protections is dynamic rather than monolithic [9] [12].