Results from the first academic study of the technique shows that it can increase success rates in negotiations with both men and women by as much as a third.
Effective feminine charm combines flirtation with friendliness and women who get it right can get around 20 percent off the price of a car, according to the study.
But getting the right balance between flirting and being friendly is vital, because women who are too straightforwardly friendly lose out, according to Laura Kray who led the study.
Researchers from the University of California, Berkeley, and the London School of Economics, carried out four separate experiments to investigate female charm, the newspaper added.
They say that, while there is a commonly held assumption that feminine charm boosts a woman's effectiveness in negotiations, it has not until now been investigated by researchers.