In 1994 she won the Spanish Ladies Amateur and a bronze medal at the Espirito Santo Trophy.

In 1994, she captained the winning Swedish team at the European Lady Junior's Team Championship and represented Sweden at the Espirito Santo Trophy at Golf National in Paris, France, where she finished as bronze medalist together with Sofie Eriksson and Maria Hjorth.

[1] Jonasson played on the Swedish Golf Tour as an amateur and won the Rörstrand Ladies Open in 1994.

In 1997, she recorded a T4 at the Ladies Swiss Open and a solo fifth place at the American Express Tour Player's Classic in England, and finished the season ranked a career high of 36th.

[5] After retiring from tour, Jonasson became a PGA Teaching Professional based in Malmö and changed to her married last name of Carlsson.