The Numbers Behind Calgary’s Secondary Suite Boom
Calgary’s rental market has been tightening steadily since 2023, and secondary suites have become one of the most reliable income-generating home improvements available to homeowners. But does the math actually work? We break down the real costs, real rental income, and real ROI of building a legal secondary suite in Calgary in 2026.
What Does a Legal Suite Cost to Build?
Based on OAF Construction’s project data across Calgary, the typical cost of a legal basement secondary suite in 2026 ranges from $65,000 to $120,000. The variation depends on several factors:
- Suite size. A 500 sq ft one-bedroom suite sits at the lower end; a 900 sq ft two-bedroom suite with full kitchen and separate laundry approaches the upper end
- Existing conditions. Homes with existing rough-ins for plumbing and egress windows cost less to convert
- Finish level. Builder-grade finishes versus premium materials can account for a $15,000 to $25,000 difference
- Fire separation. Older homes may require more extensive work to achieve the 1-hour fire-rated separation required by code
- Permits and engineering. Typically $2,500 to $4,500 depending on scope
After accounting for the City of Calgary’s SSIP rebate of up to $10,000, the net investment for most homeowners falls between $55,000 and $110,000.
What Can You Charge in Rent?
Calgary’s secondary suite rental market in 2026 shows strong demand and rising rates:
| Suite Type | Average Monthly Rent |
|---|---|
| 1-bedroom basement suite | $1,200 to $1,500 |
| 2-bedroom basement suite | $1,500 to $1,800 |
| 1-bedroom with separate entrance and parking | $1,400 to $1,700 |
| 2-bedroom with in-suite laundry | $1,700 to $2,000 |
These figures are based on current listings in Calgary’s established neighbourhoods including Tuscany, Panorama Hills, Coventry Hills, McKenzie Towne, Auburn Bay, and Midnapore. Inner-city and Beltline-adjacent areas may command premiums of 10 to 20 percent.
ROI Calculation
For a typical scenario. A $85,000 legal suite build with SSIP rebate, rented at $1,500 per month:
Annual rental income: $18,000 Less vacancy (5%): -$900 Less maintenance and repairs (5%): -$900 Less insurance increase: -$300 Less utilities increase: -$1,200 Net annual income: $14,700
Net investment (after SSIP): $75,000 Simple payback period: 5.5 years Annual cash-on-cash return: 19.6%
This does not account for the increase in property value, which typically adds 15 to 25 percent to the home’s assessed value. Often exceeding the cost of the suite itself.
Property Value Impact
Real estate appraisers in Calgary consistently value legal secondary suites as a significant property improvement. A home purchased for $500,000 that adds a legal suite costing $85,000 will typically appraise at $575,000 to $625,000. A net value increase of $75,000 to $125,000 above the original price, even before accounting for rental income.
The key word is “legal.” Unpermitted suites receive little to no value in a formal appraisal, and they can actually reduce a home’s marketability by creating liability concerns for buyers and their lenders.
Tax Considerations
Rental income from a secondary suite is taxable in Canada. However, you can deduct a proportional share of expenses against that income:
- Mortgage interest. Proportional to the suite’s share of total home square footage
- Property taxes. Same proportional calculation
- Insurance. The incremental cost of adding the suite
- Maintenance and repairs. Costs directly related to the suite
- Capital Cost Allowance (CCA). You can depreciate the construction cost, though this has implications when you sell
Consult a tax professional for your specific situation, but the tax-advantaged nature of rental income makes the effective return even stronger than the gross numbers suggest.
The Bottom Line
A legal secondary suite in Calgary delivers one of the strongest risk-adjusted returns available to homeowners. With payback periods of 4 to 6 years, annual returns approaching 20 percent, and significant property value increases, the investment case is compelling. Especially with the SSIP rebate reducing your upfront cost.
The critical factor is building it legally, to code, with proper permits and inspections. This protects your investment, qualifies you for the SSIP rebate, maximizes your property value increase, and ensures your insurance coverage remains valid.
OAF Construction specializes in legal secondary suite development across Calgary. Contact us for a free consultation and fixed-price quote.