Among his architectural achievements are St Catherine's College, Oxford, work at Merton College, Oxford, the Radisson SAS Royal Hotel, Copenhagen, the Danish National Bank building in Copenhagen, The Royal Danish Embassy in Knightsbridge, London as well as a number of town halls and other buildings in his native Denmark. Jacobsen has created a number of highly original chairs and other furniture.

Many of Jacobsen's furniture designs have become classic, including the Ant chair from 1952 and the Swan and the Egg which were both designed for the Radisson SAS Hotel. Jacobsen is, however, perhaps best known for the Model 3107 chair of 1955, known also as the "Number 7 Chair" which has sold over 5 million copies.