The Home Almanac

Vol. I, MMXXVIThe Canadian home, in season655 stations, every province and territory

Pool Calendar

When to open, when to close, and when to winterize before the first frost. Computed for your exact place from the 30-year climate record at your nearest station.


Open around Set your place
Close / winterize
Season length

Open, close, and a ten-day winterize reminder.

Opening weekend watch: Check the live forecast and work windows for your place on the Weather page before you pull the cover off.

American Homestead Summer, a Currier and Ives lithograph of a farmhouse in full summer
American Homestead Summer. Currier and Ives, New York, 1868.

Pool dates for major cities

Computed from each city's own station normals. Your town's dates may differ; use the planner above for your exact place.

CityOpen aroundClose / winterizeSeason
Victoria BC June 18 September 24 98 days
Vancouver BC June 8 September 27 112 days
Kelowna BC June 2 September 18 108 days
Calgary AB June 29 September 2 65 days
Edmonton AB June 28 August 29 62 days
Saskatoon Diefenbaker SK June 10 September 5 87 days
Regina SK June 7 September 2 87 days
Winnipeg Richardson MB June 4 September 12 100 days
Sudbury ON June 6 September 15 101 days
Ottawa Cda ON May 24 September 25 124 days
Toronto Lester B. Pearson ON May 26 September 29 127 days
Windsor ON May 15 October 7 145 days
Montreal/Pierre Elliott Trudeau QC May 25 September 26 124 days
Quebec/Jean Lesage QC June 7 September 13 99 days
Fredericton NB June 8 September 15 99 days
Halifax Stanfield NS June 14 September 23 101 days
Charlottetown PE June 19 September 21 94 days
Whitehorse YT n/a n/a n/a
Yellowknife NT June 29 August 20 52 days

Method: monthly mean temperature normals anchored mid-month, linear interpolation across 15 C (open) and 13 C (close), capped ten days before first frost. Read the full methodology.

Questions, answered plainly

When should I open my pool in Canada?

Open once the monthly mean temperature has settled above about 15 C and nights are reliably mild. In Toronto that is usually the second half of May; in Montreal or Ottawa, late May; in Calgary or Winnipeg, late May to early June; on the BC coast, April to early May. The date is computed from the 30-year climate record at your nearest station, not a national average.

When should I close and winterize my pool?

Close while the water is still warm enough to winterize properly, but no later than about ten days before the first hard frost. The tool above gives both the temperature-based close window and the frost hard-stop for your place. A freeze in the plumbing is the expensive mistake; the winterize date is the one to put in your calendar.

Can I keep a pool open year-round in Canada?

Only in mild coastal climates where winter monthly means stay high enough that the water rarely cools below 13 C. For most of the country the answer is no; the tool flags the few places where year-round is realistic.

How is the pool season length calculated?

From the spring crossing of 15 C to the earlier of the fall crossing of 13 C or ten days before the average first frost. It is a climate average, not a guarantee: watch the forecast and adjust for the season.