When Should You Open and Close Your Pool in Ontario?

If you’re a pool owner in Ontario, timing your pool opening and closing is one of the most important parts of maintaining your swimming pool. Opening your pool too early can lead to unnecessary costs, while closing it too late may result in damage from freezing temperatures. In this guide, we’ll break down the ideal times to open and close your pool in Ontario, and why getting the timing right protects your investment and keeps your pool in top shape.

🏊‍♂️ When to Open Your Pool in Ontario

Best Time to Open: Late April to Mid-May

In Ontario, the ideal time to open your pool is between late April and mid-May, when temperatures consistently stay above 15°C and the risk of frost has passed.

Benefits of Opening Your Pool at the Right Time:

• Prevents algae growth: Warm weather and stagnant water can lead to algae buildup. Opening early helps avoid a green, murky pool.

• Easier water balancing: Cooler temperatures make it easier to balance your pool chemistry before the swimming season kicks off.

• More time to enjoy your pool: Early opening gives you more days to enjoy your backyard investment.

• Ready for the long weekend: Many Ontario homeowners aim to open by the Victoria Day long weekend, the unofficial start to pool season.

📍Tip: If you use a mesh safety cover, consider opening your pool even earlier. Sunlight passes through mesh, encouraging algae growth beneath.

❄️ When to Close Your Pool in Ontario

Best Time to Close: Mid-September to Mid-October

In Ontario, the ideal time to close your pool is when water temperatures fall below 15°C (59°F). This typically happens between mid-September and mid-October, depending on your location.

Why Proper Timing Matters:

• Protects equipment from freezing: Closing too late can expose pipes, filters, and heaters to freeze damage.

• Maintains water clarity: Cooler water requires fewer chemicals and reduces the risk of algae blooms under your pool cover.

• Easier spring opening: A properly closed pool leads to a faster, cleaner, and less expensive opening next season.

📍Tip: Avoid closing too early — warm water left stagnant under the cover can lead to cloudy or algae-filled water by spring.

✅ Professional Pool Opening & Closing Services in Ontario

At AquaCare Pools, we specialize in pool opening and closing services across the Greater Toronto Area and surrounding regions. Our experienced team ensures your pool is opened and closed properly, protecting your system and saving you time and money.

Our Seasonal Pool Services Include:

• Pool heater start-up and shutdown

• System pressure testing and inspections

• Water balancing and chemical treatment

• Cover removal and secure winterization

• Skimmer line and pipe blowout

• Gas line safety checks (by TSSA-certified technician)

📅 Book Your Pool Opening or Closing Today

Avoid the stress and guesswork. Let AquaCare Pools handle your seasonal pool maintenance with expert care.

📞 Call us at (647) 669-7819
📧 Email: info@aquacarepools.ca

Serving the GTA & Surrounding Areas