Highest and best use
Highest and best use is the reasonably probable use of a property that is physically possible, legally permissible, financially feasible, and maximally productive. A highest and best use analysis compares options that pass all four tests.
The largest building allowed by zoning does not automatically create the most value.
The four tests of highest and best use
The Appraisal Institute of Canada’s CUSPAP standards, effective April 1, 2026, define highest and best use through these four tests. California’s Board of Equalization also describes the four tests in its appraisal guidance. Apply them to each candidate use before comparing value.
Four tests, and the evidence a development screen needs
| Test | Question | Evidence to check |
|---|---|---|
| Physically possible | Can the use fit and function on this site? | Lot dimensions, terrain, access, servicing, existing buildings, and a plausible building envelope. |
| Legally permissible | Is the use permitted, or is a change reasonably probable? | Zoning, overlays, title restrictions, approvals, and the evidence and timing for any proposed change. |
| Financially feasible | Does the use support its costs and required return? | Market demand, achievable revenue, construction costs, municipal charges, financing, and risk. |
| Maximally productive | Which feasible use produces the greatest value? | Compare the remaining options on a consistent valuation date and set of assumptions. |
A worked example: duplex, fourplex, or six units
Assume a vacant lot offered at CAD 450,000. A duplex and a fourplex are permitted and physically fit. Six units would require an unapproved rezoning. These are illustrative underwriting assumptions, not a valuation of a real property.
For this simplified comparison, residual land value = completed project value − non-land development costs − required developer profit. Non-land costs include construction, professional fees, financing, municipal charges, contingency, and selling costs. Land and developer profit are counted separately. A real appraisal may need discounted cash flows and further adjustments.
Illustrative residual land value, all amounts in CAD
| Option | Completed value | Non-land costs | Required profit | Residual land value |
|---|---|---|---|---|
| Duplex | 1,900,000 | 1,350,000 | 250,000 | 300,000 |
| Fourplex | 2,800,000 | 1,900,000 | 400,000 | 500,000 |
| Six units, conditional on rezoning | 3,900,000 | 2,900,000 | 550,000 | 450,000 |
Turn the comparison into a go/no-go decision
At the assumed asking price, the duplex misses the required return by CAD 150,000. The fourplex leaves a CAD 50,000 buffer. The six-unit option has no buffer and still depends on rezoning. Among these candidates and assumptions, the fourplex has the highest residual land value and merits further diligence.
That buffer is small enough that a cost increase, lower sale price, or an overlooked charge could change the decision. Test those inputs before committing. More units alone do not establish highest and best use.
Bucky helps with the early go/no-go screen by connecting an address to available site facts and zoning sources. Use those facts to identify plausible options and unresolved constraints, then verify the physical design, approvals, and economics. Check coverage for the address before relying on a result.
As vacant, as improved, and subject to approvals
For an improved property, compare retaining or adapting the existing building with redevelopment. Demolition costs, lost income, and timing can make the best use as improved different from the best use of the land as vacant. CUSPAP addresses both analyses.
A proposed rezoning is an assumption that needs evidence. CUSPAP requires consideration of the probability and imminence of a change to land-use controls. Keep an approval-dependent option separate from an option already permitted, and record what would need to happen before it could proceed.
Sources reviewed October 8, 2026. Bucky’s preliminary site screen supports the analysis; it does not replace a professional appraisal or establish municipal approval.
Free toolWhat is my property zoned for?Zone code, permitted and conditional uses, and the overlays that modify them — cited to the bylaw section.Try it →Common questions
- Is highest and best use the maximum density allowed by zoning?
- No. Maximum density is one legal constraint. A smaller project can have a higher residual land value if the additional density costs more than it earns or cannot be delivered physically.
- What should I check first in a highest and best use analysis?
- Identify candidate uses, then check legal permission and physical fit before spending heavily on underwriting. Record missing information and approval-dependent assumptions rather than treating them as passed tests.
- Can highest and best use assume a rezoning?
- A reasonably probable change may be considered when supported by evidence. An unapproved rezoning should remain a conditional scenario with its probability, timing, costs, and risks stated.
- Is a Bucky go/no-go screen a highest and best use appraisal?
- No. A site screen helps identify constraints and candidate uses for further diligence. A highest and best use appraisal also requires professional judgment and a supported comparison of market value, costs, and returns.