Jonas Osslund studied at Nyckelviksskolan from 1977-78 and at Capellagården from 1979-82. In 1982 he got his apprentice diploma in cabinetmaking, and two years later he began his studies in interior architecture and furniture design at the Konstfack University of Arts, Crafts and Design in Stockholm from where he graduated in 1988. One year after graduated Osslund and four other young designer were invited to the manufacturer Lammhults for a one-year collaboration in the project Lammhults Workshop. Osslunds contribution was the chair Da Capo made of steel pipes and a spring steel back, which was awarded the Excellent Swedish Design in 1991.
During 1987 Osslund was a guest student at the Fashion Institute of Technology and the department of interior design in New York. After graduation, Osslund joined Tengbom Architects, from where he continued to the architectural office of Erik Ahlsén. In 1992 Osslund founded his own interior architecture and furniture design studio in Stockholm from where he works mainly with public environments.
While still at Konstfack Osslund began a collaboration with Mårten Cyrén. In 1990 they designed the café chair Klyka together for Miljöexpo that is a part of the collection at the Swedish Nationalmuseum and at the Museum of Furniture Studies. Klyka was given the Excellent Swedish Design award the same year. In 2001 Osslund and Cyrén also designed the armchair and sofa Ellips.
Osslund designed pieces on his own for Miljöexpo including the design of the chairs Jack and Colt in 1991. For NC Nordic Care he designed the chair Alva in 2018 and the table collection Grace. As an interior architect Osslund has worked on Villa Nockeby and Nordbanken in Stockholm.
Besides his work as a designer, Osslund was appointed professor at LiU Malmsten (2009-12) and later a lecturer in furniture design at Konstfack (2013-21).