The rules, in full
Every rule the engine applies, written down.
The calculators are the interactive half of this; these are the citable half. One page per rule, longer than an FAQ answer, with the CRA source named and the date it was last read against what is written here. There is also a page for the rules we do not compute, which is the section an accountant checks first.
The rules
Can a corporation claim GST/HST on the mileage it pays its owner?
A GST/HST registrant that pays an allowance based solely on business kilometres is deemed by ETA s.174 to have paid tax inside it, and claims the tax fraction of the allowance: 5/105 where only GST applies, 13/113 in Ontario and 15/115 in the Atlantic HST provinces.
How much of a client meal can a Canadian corporation deduct?
Section 67.1 of the Income Tax Act limits the deduction for food, beverages and entertainment to 50% of the amount paid, tip included, and the input tax credit on that expense is limited to 50% of the GST/HST in the same way.
How many staff events a year are 100% deductible?
CRA accepts six employer-paid social events a year, each open to all employees at a given location, as 100% deductible and free of a taxable benefit; the seventh and later events in the same year fall to the ordinary 50% limit on food, beverages and entertainment.
What is the taxable benefit when the company owns the car?
When a corporation owns or leases a car its owner also drives personally, that person receives a taxable benefit: a standby charge of 2% of the car's cost for each 30-day period it was available — or two-thirds of the monthly lease cost — plus an operating expense benefit of 34¢ for every personal kilometre driven in 2026.
How much can a corporation claim on equipment in the year it buys it?
Capital cost allowance is claimed on a declining balance at the class rate — 55% for computers in class 50, 20% for class 8 equipment — and for property acquired before 2028 the accelerated investment incentive suspends the half-year rule, so the whole cost enters the first year's base.
What does a corporation have to keep, and what makes a receipt good enough?
A corporation keeps its books, receipts and supporting documents for six years from the end of the last tax year they relate to, and an input tax credit needs a document showing the supplier's GST/HST registration number once the purchase reaches $100.
What has to come across when you move your books to a new tool?
Changing bookkeeping systems changes nothing about what has to be kept: subsection 230(4) of the Income Tax Act requires business records to be held for six years from the end of the latest year they relate to, in an electronically readable format, and CRA puts that duty on the business rather than on the software it used.
What LedgerLodge does not compute
The boundary, stated plainly: no filing, no payroll, no home-office allocation, no salary-against-dividends, and no rule applied before it is enacted.
How to read these pages
- Every rate is dated. These pages were checked against the linked CRA sources, each on or since 7 September 2026, and every rule page prints the day each of its own sources was read. A rule stated without a date becomes wrong on its own, usually the following January.
- The engine is the authority, not the page. Each rate here is a display copy of a dated row in the calculation engine, which is what actually produces a number. If the two ever disagree, the page is the one that is wrong.
- A rule is not advice. These describe what the CRA publishes and what the product applies. Whether a rule reaches your situation is a question for a Canadian CPA.
- LedgerLodge does not file. It keeps the books, the receipts and the evidence, and prepares the workpapers a return is built from. Filing is someone else’s signature.