Tankless vs Tank Water Heater: Which Saves You More?

The "tankless saves you money" pitch isn't always true. Here's the honest comparison for an Ontario household.

Upfront cost (installed, GTA, 2026)

• **Tank, 50 USG, gas, mid-tier:** $2,200–$2,800
• **Tank, 50 USG, electric, mid-tier:** $1,800–$2,400
• **Tankless, gas, condensing, mid-tier:** $4,500–$6,500

Tankless costs roughly 2x to install because of larger gas line, dedicated venting, and condensate drain.

Operating cost

For a 2-adult, 2-kid family using ~80 USG/day:

• Tank gas: $360–$420/year
• Tank electric: $720–$900/year
• Tankless gas: $260–$320/year

Tankless saves ~$100–$150/year over tank gas. ~17 years to recoup the upfront difference.

Lifespan

• Tank: 8–12 years before tank corrosion forces replacement
• Tankless: 18–22 years (most heat exchangers outlast two tanks)

If you're staying in the home long-term, tankless wins on lifecycle cost.

Hot water capacity

Common myth: "tankless never runs out." True only if you size it right.

• 4-person household, 1 shower at a time: 6.5 GPM tankless is fine
• 2 showers at the same time: need 8+ GPM. The bigger tankless models (Navien NPE-A2, Rinnai RU199) handle this.

Undersized tankless = lukewarm shower. Sized properly = unlimited hot water on demand.

Don't forget

• Tankless needs annual descaling in Mississauga (we have hard water — minerals coat the heat exchanger). ~$150/year service.
• Tankless requires a dedicated 3/4" gas line in most cases. If your existing line is 1/2", add ~$400 to the install.
• Some older homes have undersized electrical for an electric tankless. Stick to gas or wait until you upgrade the panel.

The honest call

• Empty nesters, low hot water demand: stick with a tank.
• Family of 4+, high demand, staying long-term: tankless pays back.
• High-end home with multi-zone bathrooms: tankless or even two tanks.
• Tight budget, replace-now: gas tank.

We'll size and quote both options on the same call so you can compare. (416) 258-2460.