The city declared an extreme cold weather alert earlier this week and that remains in effect. The alert is issued when the city feels it is life-threatening for the homeless to be out in the cold.
On Wednesday morning the temperature slipped to -21 C — with the wind chill it felt more like -28 C.
And although it was frigid, it was a long way off the record -31.1 C set back in 1976.
The bitter cold is expected to hang around until next Monday.
The cold is taking its toll on infrastructure around the city.
A water pipe burst at a downtown hotel on Wednesday, leaving behind a watery mess.
Other pipes are freezing making it a "pretty crazy" few days for plumber Steve Glasgow.
He's says every time the mercury dips pipes — especially in older homes — freeze.
It's irritating and inconvenient for the homeowner. It also means a bill for about $350.
The cold snap is also frustrating for commuters, making it feel as if their daily commute is taking longer.
But the TTC says there haven't been any major delays. And TTC spokesperson Jessica Martin says commuters can look on the TTC website and "check your route before you leave your house."
And the city is also testing a new salt mixture for the roads — one that mixes salt with beet juice and might work better in the bitter cold.
"It's not very often that Toronto gets less than -20 C," said Pete Noehammer, who works for the city's transportation services. "But when it does we want something we can go to for an effective chemical."
So far, the city says, it has used almost 5,000 tons of salt to keep the roads ice-free.