It is recorded that in 1858 Streetsville had a population of over 1,500 and was incorporated as a village. By the late eighteen hundred, the population was around 2000.

Many of the families that helped to develop Streetsville still have family in Streetsville today.

Just before the turn of the century Streetsville was a very busy village. There were doctors, a veterinary, a hardware and general store, tailors and blacksmiths, hotels, liquor stores, churches, schools, post office, a library and its own newspaper, the Streetsville Review, to name a few.

A decline set in when the Great Western Railway [now CPR] was built bypassing Streetsville. Business was diverted away from the village and the population dwindled to about 670. When the Credit Valley Railway came in 1879 it raised great hopes, but it came to late to save many of the earlier industries.

Over the years Streetsville was plagued with fires that crippled much of the remaining business. The Barber Mill burned in 1861 and the Flax Mill burned in 1867. Both the Globe Hotel and the Stephen House Hotel were destroyed by fire in 1876 and the Robert Graydon store and the post office were burned in 1909.

New industries started to arrive and over time the village grew once again. When William Couse arrived in Streetsville, he started beekeeping and in 1884 set up his coal, grain and seed business. The quality of his honey brought fame to Streetsville and his seeds were shipped world-wide.

During these years Streetsville had wooden sidewalks and coal oil lamps. By 1904 cement sidewalks were replacing the wooden ones. After the turn of the century a new dam was constructed, and a generator installed in the walls of the old Flax mill. The water supply was operated from the same generator, so the village was supplied with both water and electricity. The first filtration plant was built in 1946 and a sewage disposal plant shortly after.

The Cenotaph was erected in 1926 and three years later Joseph Phair erected a building for the Metropolitan Bank located on the corner of Queen and Thomas Street. It was taken over by the Bank of Nova Scotia in 1915. The Royal Bank was opened in 1955. In January of 1962, Streetsville gained the status of a town with a population of 5000 and Frank Dowling became the first mayor. Mr. Dowling was also the first Deputy Reeve of Streetsville.