From 2010 to 2013 Anja Piel was party chairwoman of Bündnis 90/Die Grünen of the state association of the Lower Saxony (Niedersachsen) and from 2013 to 2020 member of the state parliament of the Lower Saxony (Niedersachsen) and chairwoman of the parliamentary group Bündnis 90/Die Grünen. Since 2020, she is a member of the Federal Executive Committee of the Confederation of German Trade Unions (Deutscher Gewerkschaftsbund DGB). She is responsible for labour market and social policy/law, migration and anti-racism policy, project “Fair Mobility” and DGB-Rechtsschutz GmbH. Since 2020, Anja Piel has been alternating Chair of the Administrative Council of the Federal Employment Agency (Bundesagentur für Arbeit) and alternating Chair of the Federal Executive Board of the German Pension Insurance Federation (Deutsche Rentenversicherung).
Anja Piel has been a member of the Social Advisory Council since 2021 and has become second deputy chair in 2024.