About Dario A.
Dario A. Castañeda practices law in Illinois and works at N400 Harbor Immigration Law, PLLC. He is known in his community for steady, practical handling of immigration matters. He deals with the paperwork, the interviews, and the deadlines that make immigration work exacting and immediate.
Castañeda completed his legal training before entering practice in Illinois. He took the steps required to become a licensed attorney and moved into immigration law early in his career. That background underpins the casework he handles today and informs how he prepares clients for immigration processes.
Over time he has handled a range of immigration matters. His practice includes naturalization petitions, family-based immigration requests, asylum and humanitarian relief applications, and defense in removal proceedings. He often prepares applications and supporting evidence for filings with U.S. Citizenship and Immigration Services and related agencies.
He approaches each case with a focus on clear communication. He explains options in plain language. He helps clients understand timelines, likely outcomes, and procedural requirements. He drafts and reviews filings, prepares clients for interviews and hearings, and works to keep cases moving through administrative systems.
At N400 Harbor Immigration Law, PLLC he represents individuals, families, and small groups. The firm’s name signals particular attention to naturalization matters, but his work extends across the common types of immigration relief. He coordinates document collection, files petitions, and responds to requests for evidence when agencies seek more information.
Outside of courtrooms and government offices, he spends time meeting clients and explaining next steps. His practice is rooted in daily case management and procedural clarity. As of 2026 he practices immigration law at N400 Harbor Immigration Law, PLLC, handling naturalization and related immigration matters.