New Furnace Cost in Mississauga (Installed Prices)

Most Mississauga homeowners replacing a gas furnace are quoted between $4,500 and $7,000 installed. The published price lists run wider at both ends: EcoFrost Heating and Cooling still advertises $2,800 for a basic 80% AFUE unit (a unit federal law no longer allows in an ordinary house, see below) and $9,500 for a top-tier Carrier at 98.5% AFUE, and Furnace King Home Comfort puts the typical GTA replacement at $3,000 to $8,500. On top of that you owe the City of Mississauga a flat $244.00 permit fee, and in August 2026 there is no rebate for a gas furnace on its own: the programs that used to pay one have closed.

What a new furnace costs in Mississauga, installed

These are prices the companies publish themselves, each attributed so you can check it.

Three things fall out of that table. The cheapest row is not an option. Canada's Energy Efficiency Regulations, 2016 have required ≥95% AFUE for gas furnaces manufactured on or after July 3, 2019 (SOR/2016-311, s. 259, item 2.1). The only carve-out is a "replacement non-condensing gas furnace", which s. 257 defines as one "marked for use as a replacement for a non-condensing gas furnace in a manufactured home". So for a detached, semi or townhouse in Mississauga an 80% unit is not on the menu. EcoFrost's own guide says the same thing: "municipal code in most GTA cities requires 95% AFUE or higher for new furnace installations." The 80% rows below are what the vendor still publishes, not what you can buy. So the efficiency "step" from $2,800 to $4,500-$7,000 is not a choice you get to make. Brand tier costs as much as efficiency: EcoFrost's Mississauga page prices four 96%-and-up furnaces from $3,200 to $9,500, and the cheapest and the dearest do the same job in the same basement. And the mid-market is tight: Custom Contracting says most Mississauga homeowners pay $4,500 to $6,500, and Reliance Home Comfort puts most Canadian gas furnace buyers in the $5,000 to $7,500 range.

Watch what the number includes. EcoFrost's Mississauga prices cover equipment, all labour, gas line connection, venting, electrical, the permit and old furnace disposal: the list to hold every other quote against.

What Mississauga's housing stock does to the price

Mississauga had 244,575 occupied private dwellings at the 2021 Census. The City's own housing inventory, published with its growth forecasts, splits a near-identical 243,515 total into 127,562 detached and semi-detached homes, 36,779 townhouses and 79,174 apartments. So 79,174 of 243,515, near enough one in three, are apartments where this question never arises. The furnace market is the other 164,341 homes (127,562 + 36,779 = 164,341), fed by Enbridge Gas. Two features of that stock drive real money.

The ducts were sized for a bigger, dumber furnace. Drop a correctly sized modern unit into an older Mississauga subdivision house and the ducts, grilles and trunk sizes all have to be checked. The City's own Data Sheet for Residential Furnace Replacements makes the installer write down Total Building Heat Loss and Total Building Heat Gain, the existing and new unit input and output in BTUH, trunk sizes at the plenum, return grille free area, and a design temperature rise that "shall not exceed manufacturer's maximum or 90°F, whichever is less".

The chimney is the hidden line item. In an older house the furnace and the gas water heater usually share one masonry chimney. Move the furnace to a 96%+ condensing unit venting in plastic out a side wall and the water heater is left alone on a flue far too big for it. The City's data sheet is explicit: where an existing masonry chimney is used, "its condition must be verified for safety and an approved liner or vent shall be installed to comply with the Energy Act, as appropriate." RenoHouse, which does this work across Toronto and the GTA, publishes $1,800 to $2,400 for a single 6-inch stainless flexible liner on a 30-foot run for a gas appliance, a line that belongs on the quote before installation day.

The permit: $244, and when Mississauga makes you get one

Mississauga's list of projects that need a permit includes "furnace replacement that's of a higher efficiency than existing", "furnace ducts being altered" and any HVAC system. That first line catches nearly every real replacement: an old 80% furnace replaced by a 96% one is, by definition, higher efficiency than existing.

The fee is in Schedule B of the Building By-law, 2026 edition, under Miscellaneous Work:

• Furnace replacement: $244.00 flat fee per unit.
• Full heating system replacement (for a house): $244.00 ($428.00 for other than a house). Duct work only: $244.00; alterations to mechanical systems such as a space heater or exhaust fan, $428.00 per unit.
• Residential permits have a floor of $244.00 either way; non-residential ones $386.00.

You pay a $50 non-refundable administrative fee online and the City credits it toward the total, so a straight swap costs $244.00 all in, not $244.00 plus $50. The City wants a Residential Furnace Replacement form, plus Heat Loss Calculations and an HVAC sample drawing if you are altering ducts.

Time frames are the part contractors gloss over. The City publishes a prescreen review of 7 to 10 business days, a first residential review of 10 business days, and an average of 7 weeks to issue a residential alteration permit on a detached or semi; each resubmission cycle "could add two or more weeks". EcoFrost's Mississauga page claims turnaround is typically 1 to 3 business days for standard replacements. Plan around the City's numbers: in a January no-heat emergency the paperwork trails the installation.

The gas work itself must be done by a technician holding a TSSA fuels certificate: G.1, G.2 or G.3.

Rent or buy: the arithmetic

Rental removes the up-front number, and both major providers publish enough to do the sums.

Enercare advertises a furnace "starting from $3,995 including standard installation and 1-year warranty" against a rental "starting from $67 per month", and its own FAQ says a furnace lasts typically 15 years. Fifteen years is 180 months, so $67 × 180 months = $12,060, against $3,995 to own the same tier of equipment: a gap of $12,060 less $3,995 = $8,065.

Reliance Home Comfort publishes both columns side by side. A single-stage gas furnace is $4,500 to $6,000 installed or $75 to $90 a month to rent; a two-stage is $6,000 to $8,000 or $90 to $130 a month; a modulating unit is $8,400+ or $115 to $140 a month. Take the cheapest rental line: $75 × 180 months = $13,500, less the $4,500 purchase price of the same furnace, is $9,000.

Rental is not pure loss: it covers repairs and maintenance for the life of the agreement, and there is no up-front cost. But price the maintenance honestly. EcoFrost publishes a furnace tune-up at $149; fifteen of those is 15 × $149 = $2,235, roughly a quarter of the $9,000 gap above.

Two cautions. Rental rates are usually quoted before HST. And neither company publishes a buyout schedule. Enercare's FAQ confirms you can buy the furnace later but refers you to "the terms in your rental agreement related to equipment buyout". Get that number in writing, in dollars, before you sign.

The rebates that exist in August 2026

There is no rebate for replacing a gas furnace with a better gas furnace. The upgrade list on the Home Renovation Savings site, the program Enbridge Gas and Save on Energy run with Ontario government support, has no furnace line on it at all: heat pumps up to $12,000, insulation up to $7,700, solar and battery storage up to $10,000, attic insulation $1,000 or $1,250, heat pump water heaters $500, air sealing up to $250, windows and doors $100 per rough opening, smart thermostats $75 or $100, appliances up to $200, and $600 back on a home energy assessment. The program's help pages close the door explicitly: where a heat pump is paired with a gas furnace, "the backup heating system is not eligible for the rebate; only the heat pump system qualifies."

The programs that did pay for high-efficiency furnaces are finished. Enbridge Gas's Home Efficiency Rebate ended intake on January 27, 2025. Home Efficiency Rebate Plus closed to new applicants on February 5, 2024, required post-retrofit assessments by December 1, 2025, and would not process anything submitted after December 31, 2025.

What a gas-heated Mississauga household can still claim:

• A heat pump, if you add one. For an Enbridge Gas customer heating with natural gas, a cold climate air source heat pump pays $500 per ton up to $2,000 and a ground source heat pump $3,000. Those figures rise to $1,250 per ton up to $7,500 and $2,000 per ton up to $12,000 only for homes heated with electricity, oil, propane or wood.
• A smart thermostat. Enbridge Gas's own program offers a $75 instant rebate; Home Renovation Savings lists $75 or $100.

How to spot a padded quote

Five other things to check:

1. No heat loss number. The City's data sheet has a box for Total Building Heat Loss. Ask what went in it: "we always put in a 100,000 BTU unit for a house this size" is a guess, and an oversized furnace short-cycles for fifteen years.
2. A permit line well above $244.00. That is the City's whole fee for a furnace replacement. Anything materially higher is the contractor's paperwork charge, which should be labelled as such.
3. Charging separately for what others include. Gas line connection, venting, electrical, permit and disposal sit inside EcoFrost's published Mississauga price. As extras, they made the headline number look smaller.
4. An after-hours premium presented as fixed. EcoFrost publishes a $0 overtime surcharge on evening and weekend calls, so it is negotiable.
5. No chimney answer. If the water heater stays on the old chimney, ask now what the liner costs.

If you are just over the border

Fees are municipal. Brampton charges $326.21 for its standard 10-day permit application service on changes to heating and ventilation systems, and wants heat loss and gain calculations and a ventilation design summary up front. Check your own city's schedule before accepting a permit line on a quote.