Mega Deduction Calculator

Buildings and additions: excluded

Buildings in Classes 1 and 3, including additions and alterations, are excluded from the Mega Deduction. The separate Budget 2025 measure for eligible manufacturing or processing buildings (90% floor space used for M&P) is a different, time-limited rule.

Examples of buildings, additions and structural alterations

  • office and warehouse buildings
  • additions and structural alterations
  • most leasehold improvements to structures

Planning tip

Split contracts so that equipment installed in a building is invoiced separately from the structural work. The equipment qualifies even though the building does not.

CCA Class 1 / 3 · regular rate 4% declining balance · half-year rule normally applies in year one.

Calculate the deduction on buildings, additions and structural alterations

Advanced assumptions

Worked examples (Ontario)

PurchaseOld year-one deductionNew year-one deductionTax reduction, small business rateTax reduction, general rate
$25,000$500$500$56$133
$100,000$2,000$2,000$224$530
$250,000$5,000$5,000$560$1,325

Buildings and additions by province

Free: the Year-End Purchase Checklist (PDF)

One page. What qualifies, what does not, the 'available for use' trap, and the seven questions to ask your accountant before you buy. No spam, unsubscribe any time.

Year-end planning kit

The Mega Deduction Year-End Playbook

Everything you need to walk into your accountant's office with a plan instead of a question. Built for owner-managed Canadian businesses that expect a profitable 2026.

  • Excel purchase planner with every province's rates and every CCA class pre-loaded. Model up to 12 purchases, see the year-one deduction, tax reduction and 10-year comparison for each.
  • The 41-page Playbook (PDF): eligibility by asset class, the exclusions, 'available for use' rules, financing vs. leasing, recapture risk, CCPC vs. sole proprietor, and worked examples for 12 industries.
  • Accountant brief template (Word): a one-page memo you fill in and send so your accountant can confirm the plan in one email instead of a meeting.
  • 30-day action plan for purchases that must be delivered and installed before your fiscal year-end.

$97$47 CAD one-time, instant download

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Secure checkout by Stripe. Files delivered immediately after payment. Not tax advice; every plan should be confirmed by your accountant.