Area code 905 serves the populous and economically vibrant Greater Toronto Area (GTA) suburbs in southern Ontario, Canada. Introduced in 1993 as a split from area code 416, the 905 code covers cities such as Mississauga, Brampton, Vaughan, Markham, and Oshawa, which collectively form the ring around Toronto’s core. These cities have experienced explosive growth over the past three decades, driven by immigration, real estate development, and a strong business climate. The 905 area is synonymous with suburban expansion, and its residents often commute into downtown Toronto for work. It’s also home to major corporations, distribution hubs, and tech firms. As the population surged, overlays such as 289, 365, and more recently 742 were introduced to accommodate growing demand. The term "905er" even became part of Canadian pop culture to refer to suburban residents. Today, the 905 area plays a critical role in the region’s economy, contributing significantly to Ontario’s GDP and providing a high standard of living. Businesses with 905 numbers are perceived as locally grounded and accessible to GTA customers. The area code is now part of a complex overlay zone, but original 905 numbers are still seen as a mark of early presence in Ontario’s economic powerhouse suburbs.