1991-1996 he studied at Vilnius University, graduated as a journalist, and in 1994-1995 he had an internship at the University of Illinois in the USA.
In 1992-1995 J. Banys worked as a journalist at Panorama on LTV, in 1995-1998 he worked at Lietuvos rytas Television, where he produced investigative journalism programmes and video reports on the topics of national security, international relations and cultural heritage. In 1998-2007 he worked as a strategic planner at Video Advertising Studio (VRS), in 2007-2008 he worked as a creative director at LNK Television, TV Mania, and in 2008-2010 he was a programme director at LRT. Since 2010 J. Banys has been a strategic planner at the agency Adell Taivas Ogilvy.
In 2003-2007 J. Banys was a lecturer at the International Business School (IBS), where he taught history of advertising, brand strategy, basics of communication planning, etc., In 2003-2005, he delivered lecture series "Advertising", "The whole truth about the brand", "Creating and managing the brand as an asset of the company", "Psychology of advertising" at the Confederation of Industrialists' Executive Clubs in Vilnius and Kaunas, and in 2011, he delivered a lecture series "The Anglo-Saxon Theory of Film Script. In 1996-1996, J. Banys was the host and co-author of the programme "Lietuvos ryto TV", the host of the LNK television programme "If", the author of the format of the TV3 programme "Trečioji karta", the author of the script of the musical reality show "Dangus", the executive producer of the LNK programme "Ghost Hunters". J. Banys was awarded the Golden Bee for journalistic research (1995), the Ad Rem Award for the best video essay (1997), the Ad Rem Special Commission Award (1998), the Best Documentary Award of the Ministry of the Interior Competition for the film "Lithuanian Border Police" (1998), The short films "Mr Pimpis" and "What Johnny Did", based on his scripts, won the AXX Festival Competition (2005, 2006), the documentary "The Insect Trainer" (2008) and the feature-length film "Zero 2" (2010) were awarded with the Lithuanian Film Academy's Silver Crane Prize for the best screenplays. In 2016, the project "War 2020" by J. Banis and M. Starkus was recognised as the best TV documentary project in the "Pragiedruļi" competition. "Sketches of Lincoln's Country" (1995, LTV), "War Against the Silent Ones" (1997, LTV), "Lithuanian Border Police" (1998, Lietuvos ryto TV), "February 16th. He wrote the script for the documentary "Europokeris" (2002, dir. D. Ulvydas, VRS), he is the director of the documentary-animation film "Vabzdžių dresuotojas" (2008, dir. D. Ulvydas, L. Augutis, R. Miškinytė, M. Skrobecki, Era Film, Lithuania, Se-ma-for, Poland, together with broadcasters NHK, Japan, AVRO, Netherlands, Yle, Finland), co-author of the screenplay for the documentary "War 2020.
Created scripts for Tarvydas's short films at the AXX Festival-Competition "Mr Pimpis" (2005), "The Triple Sin" (2005), "What Johnny Did" (2006). J. Banys co-wrote the dialogues for the feature-length film Zero (2006, directed by E. Vėlyvis, Kino kultas).
Scripts for the feature-length films Zero 2 (co-written with A. Puklevičius and E. Vėlyvis, 2010, Kino kultas), Tadas Blinda. Home" (2011, dir. S. Aškelavičius, E. Kabaraitė, R. Marcinkus, D. Ulvydas, Litl Baz Pictures), "Redirected/ For Lithuania" (screenplay co-written by E. Vėlyvis and E. Vėlyvis, 2014, dir. E. Vėlyvis, Kino kultas), Valentinas za durų (scriptwriter together with U. Barauskaite, E. Kubilius, 2014, dir. E. Kubilius, Litl Baz Pictures, Ulvyds), The Sacred Cow (2014, dir. by D. Ulvydas, Ulvyds, Litl Baz Pictures), Emilija iš Laisvės alėjos (2017, dir. by D. Ulvydas, Fralita Films, Ulvyds), Zero III (scriptwriter with E. Vėlyvis, 2017, dir. E. Vėlyvis, "Kino kultas", "Neverever").
