Late October to mid-November, once most of the leaves are down and before the first hard freeze. Cleaning them now, in early September, mostly gets undone by the maple and elm drop in October, so if you only do it once this fall, wait.
Why the timing matters more than people think: the eavestrough is not there to look tidy, it is there to move water away from the foundation. A trough full of wet leaves in December freezes solid, meltwater backs up under the shingles, and you get the classic GTA ice dam. YS Roofing’s Etobicoke guide puts it plainly: a clean done in late September “will be undone by the bulk of maple and elm leaf fall through October,” and they recommend late October to mid-November for the fall pass, plus a second pass in late May or early June after the last frost. Houses with mature trees within about 10 metres of the roofline should plan on three cleanings a year.
The City of Toronto says the same thing on its basement-flooding pages: clean eavestroughs at least twice a year and check every elbow and outlet for debris. The city also reminds you that downspout disconnection from the sewer is mandatory for all Toronto property owners, with water directed away from the foundation walls. If your downspout still goes straight into the ground, that is a bigger problem than a dirty trough, and there is an exemption application if disconnecting is not feasible on your lot.
What it costs if you hire it out. Skypole’s Toronto price guide lists roughly $150 to $175 for a one-storey bungalow, $175 to $200 for a two-storey semi, $185 to $250 for a two-storey detached and $200 to $300 for three storeys, with $150 to $300 covering most Toronto houses. Pro Tasker’s 2026 Ontario page starts at $170 per service. Heavily clogged troughs, tricky roof access and add-ons like downspout flushing or guards push the number up. All of this is before HST.
The mistake we see most: cleaning the trough and ignoring the downspout. The trough can be spotless and the elbow at the bottom is packed with two years of shingle grit. Flush every downspout with a hose until it runs clear at the extension. While you are up there, check that the trough still slopes toward the outlet and that no hangers have pulled out of the fascia. Soft, dark fascia board means water has been sitting there for a season already.
From the crew side, the order we would do it in: downspouts and elbows first, then the troughs, then run water from the far end and watch where it goes. If it pools instead of draining, the slope is wrong and no amount of cleaning fixes that. Two storeys and up, on a ladder, in November, is where people get hurt; if the ladder has to go on a slope or over a deck, pay someone with the right equipment.
If you have had ice damming or an overflow point on your house, post a photo of the spot and what it cost you to sort out, it helps the next person budget.
What kind of trees are over your roof, and is it one storey or two? That changes whether one November cleaning is enough or you need a mid-October pass as well.
