Guide
How to check an AI answer about CRA rules: five checks
An answer about a CRA rule is a lead, not a ruling. These five checks take a few minutes and work on an answer from any AI tool. The example is a real line on a real form: advertising on T2125.
1. Does it name a source you can open?
A usable answer names the document (a form number, a guide, a section of an act), says where in it (a page, a line number or a heading) and links to it. "The CRA says" is not a source. If you cannot open the document and find the sentence, the answer is a guess you have not tested yet.
2. Is it the right edition and date for the tax year?
Forms and guides are reissued, and a rule that applied to the 2024 return may not apply to the 2025 one. Look for the edition or tax year printed on the form and the date the CRA shows for the page, and match them to the return you are preparing. An older edition is not wrong for an older return: a 2024 guide is the right one for a 2024 return.
3. Is it Canadian, and is it your client's province?
An answer that mentions the IRS, Form 1040, a W-2 or a state tax is about the United States. Inside Canada the rule can also depend on the province: GST or HST, provincial sales taxes and provincial returns differ, and Quebec has its own returns (for example TP-1 and CO-17). Check that the answer says which province it assumed.
4. Does every number appear in the source?
Open the cited passage and find each figure in it. Figures change from year to year, and a number that is not in the source is the first thing to leave out.
- The line number on the form, not only the name of the line.
- Each amount, rate or threshold, and the year it applies to.
- Each date, and what the source says about a date that falls on a weekend or a holiday.
5. Did it assume something about your client?
The same question can have different answers for a sole proprietor and a corporation, for an employee and a self-employed worker, or for one tax year and the next. A good answer states what it assumed, or asks you. If it did neither, check the case against the source yourself.
A worked example: advertising on T2125
The question: which line of T2125 is advertising? A checkable answer: "Advertising expenses go on line 8521, in Part 4 of Form T2125." Now the five checks.
| Check | What you look at | What you find |
|---|---|---|
| 1. Source | The document the answer names | T2125, Statement of Business or Professional Activities, opened as a PDF |
| 2. Edition and date | The edition printed on the form and the date the CRA gives | 2025 edition, document dated 9 February 2026: right for a 2025 return |
| 3. Country | Who issued the form | A CRA form, so Canadian |
| 4. Numbers | The line on the page | Page 3, Part 4: "Advertising" next to line 8521 |
| 5. Assumptions | Who uses the form | Sole proprietors and partners. A corporation does not use T2125; it files its own return (see the T2 guide) |
Nothing here needed a tax opinion, only the document. The line-by-line rules are in the T2125 guide.
When the document and the answer disagree
The document wins. If the document itself is unclear for your client's case, the next step is the CRA or a qualified professional. This page and any AI answer are information, not professional advice.
How Immer helps with these checks
Immer is built so that these checks are quick. Each fact in an answer carries its document, the document's date and a link, and a PDF opens at the right page (checks 1 and 2). Every figure is checked on the server against the cited passages, the documents you attached or a calculation shown on screen, and a figure it cannot trace is flagged (check 4). When the province, the year or the kind of taxpayer matters, it asks you with options to click (check 5). When the catalogue does not cover a question, it says so, and when it uses an official government website instead, it names the site.
Immer can still be wrong. The five checks apply to its answers too: open the source before you rely on one.
Questions
- Can I trust an AI answer about a CRA rule without checking it?
- No. An AI model writes from what it read or remembers, and it can misread a passage, mix up years or answer for another country. Treat the answer as a lead and open the document it names.
- What counts as a source for a CRA rule?
- A publication of the CRA or of a federal or provincial government, or legislation, read on the publisher's own site: a form, a guide, an act, a bulletin. A blog post, a forum thread or another AI answer is not a source.
- How do I know a CRA document is current for my client's return?
- Check the edition or tax year printed on the form and the date the CRA gives for the page, and match them to the return you are preparing. Older editions stay correct for older returns.
- Does this page replace professional advice?
- No. It describes a way to check information. It does not tell you what a rule means for a particular client.
Official sources
- T2125 Statement of Business or Professional Activities (2025) · dated February 9, 2026
- T4002 — Find out if this guide is for you; What's new for 2025 · dated April 16, 2026
This page explains official publications in plain words. It is informational, not professional advice, and it is not a substitute for the documents it cites: open the source before you rely on it.
Read next
- GST/HST for bookkeepers: registering, reporting periods and due datesWhen a client must register for the GST/HST, which reporting period the CRA assigns, when returns and payments are due, and why bookkeepers cannot use the quick method (RC4022).
- Form T2125 for bookkeepers: expense lines, home office, due datesT2125 expense lines by number (8521 advertising, 8523 meals, 9945 home office and more), who reports, the accrual method, records and the 2026 dates, from CRA Guide T4002.
- Payroll remittances: remitter types, due dates, late penaltiesWhat an employer deducts, regular, quarterly and accelerated remitters, when each remittance is due, late-remittance penalties and the T4 deadline, from CRA Guide T4001.
- Canadian tax deadlines: what is due, month by monthCanadian tax deadlines in calendar order: payroll remittances, T4 slips, instalments, April 30, June 15, GST/HST returns and the T2, each with the CRA guide it comes from.
- Glossary of Canadian bookkeeping and tax termsGST/HST, payroll, self-employed and corporation (T2) terms as the CRA prints them, in plain words, each with the CRA guide it comes from. Also in French, Ukrainian and Polish.
Have a question this page does not answer?
Ask Immer. It searches the same official publications, cites each one with its date, and says so when they do not cover your question.