The capital cost allowance (CCA) is Canada’s system for letting corporations expense the depreciation of capital assets against taxable income. Deducting the full purchase price of a long-lived asset in the year it’s bought would let companies zero out tax bills with big purchases, so instead the CCA system spreads the deduction over many years following a declining-balance schedule set by the CRA.
Each 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 never more.
CCA classes and rates change with federal budgets, so verify against current CRA publications for current-year tax work. 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.
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 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 blocks 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 run 25-40% of the purchase price, a big chunk of the project’s true after-tax PW.
In PW analysis you capture this with the Capital tax factor (CTF), which discounts the first cost by the present value of all future CCA tax shields, and the Capital salvage factor (CSF), which discounts the salvage value by the corresponding tax effects.