When does halftime begin? Women wonder if they're actually there yet. Officially, halftime is defined as after the age of 40, which includes 150,000 women every month entering their second half. In many respects, that age seems young as many women focus on their careers, then start their families even in their mid-thirties. Most women I work with are between 50 and 60 as they are hit hard with some of the realities of halftime.