The capital cost allowance (CCA) is Canada’s system for letting corporations expense the depreciation of capital assets against taxable income. Instead of deducting the full purchase price of a long-lived asset in the year it’s bought (which would let companies zero out tax bills with big purchases), the CCA system spreads the deduction over many years following a specific declining-balance schedule set by the CRA.
Each type of asset belongs to a CCA class, and each class has a maximum CCA rate — the largest declining-balance rate the corporation can claim in a year. Common classes:
| Class | Asset type | Max rate |
|---|---|---|
| 1 | Buildings (post-1988) | 4% (or 6% for non-residential, 10% for manufacturing) |
| 8 | General office furniture, equipment | 20% |
| 10 | Vehicles, automotive equipment | 30% |
| 12 | Tools < $500, computer software | 100% |
| 50 | Computers, laptops, software (post-2007) | 55% |
| 53 | Manufacturing/processing equipment (2016-2025) | 50% |
The rate is a maximum: a company can claim less if it wants to save the deduction for a year when it has more income to shelter, but it can never claim more.
CCA classes and rates change with federal budgets — verify against current CRA publications for current-year tax work. For example, Class 53 stops accepting new acquisitions after 2025; manufacturing equipment acquired from 2026 onward goes to Class 43 (30%) instead. The post-2018 Accelerated Investment Incentive also modifies the half-year-rule mechanics for many newly-acquired assets (see Half-year rule).
The mechanism:
- The asset goes into a pooled “class account” at its purchase price (this is the asset class’s UCC, the tax book value).
- Each year the class is allowed to deduct from taxable income (the CCA expense).
- The UCC for the next year drops by that same amount: .
- When the asset is sold, the salvage value is removed from the UCC pool. If the pool goes negative, the difference is “recaptured” depreciation, treated as taxable income.
The key wrinkle is the Half-year rule — only half the asset’s purchase price gets added to the UCC pool in the year of acquisition. This prevents the easy gaming of “buy December 31, claim a full year’s CCA on January 1.”
Why CCA matters in engineering economics. Depreciation by itself is a non-cash book entry, but the tax saving it generates is real cash. CCA reduces taxable income, which reduces the tax bill, which is a real cash inflow (well, a real reduction in cash outflow) the corporation gets to keep. Over the life of an asset, the cumulative tax savings can be 25-40% of the asset’s purchase price — a major component of the project’s true after-tax PW.
The cleanest way to capture this in PW analysis is via the Capital tax factor (CTF), which discounts the first cost down by the present value of all future CCA tax shields, and the Capital salvage factor (CSF), which discounts the salvage value down by the corresponding tax effects.
For details on the UCC accounting see Undepreciated capital cost; for the half-year rule see Half-year rule; for the present-worth factors see Capital tax factor and Capital salvage factor; for the broader tax framework see Corporate income tax.