If you are a Canadian resident who needs to file with the IRS, you probably need an ITIN, the Individual Taxpayer Identification Number. The form is W-7, the route from Canada is mail or a Certified Acceptance Agent, and the reason you tick on the form decides which documents you must attach. This post walks through the decision tree most Canadian articles skip.
Five Canadian personas that need an ITIN, and one that does not
There is no single "Canadian who needs an ITIN." Five distinct personas show up on the search results, and the W-7 reason box is different for each.
- Single-member LLC owner filing Form 5472 with a pro-forma 1120. ITIN is required when the LLC has reportable transactions. W-7 reason is h, Other, with Exception 1(d).
- Treaty benefits claimant reducing US withholding on royalties, dividends, or pension. W-7 reason is a, Nonresident alien required to claim a tax treaty benefit, paired with Form 8233 or W-8BEN.
- US rental property owner filing Form 1040-NR with Schedule E. W-7 reason is b, Nonresident alien filing a US tax return.
- Tax treaty Article XXIX-A claimant, typically a Canadian spouse or dependent listed on a US return. W-7 reason is e or f, depending on relationship.
- Canadian who sold US real estate, FIRPTA withholding recovery. W-7 reason is b, paired with Form 1040-NR.
The persona that does not need an ITIN: a Canadian formed a US LLC but has not yet had any reportable transactions and is not yet filing 5472. Forming the LLC alone does not trigger ITIN. Some agents oversell this by pushing ITIN at formation. You can wait until the first 5472 is actually due.
ITIN vs Canadian ITN vs SIN, clearing up the confusion
Google ranks the wrong page on the first results screen for this query, because three different numbers share similar names.
| Number | Issuer | Purpose | When you need it |
|---|---|---|---|
| ITIN | US IRS | US federal tax filing for non-US persons without SSN | 5472, 1040-NR, treaty claim |
| ITN | Canada Revenue Agency | Canadian tax filing for non-residents of Canada | Filing T1 as a non-resident of Canada |
| SIN | Service Canada | Canadian residents and workers | Working in Canada, T4 |
If you live in Canada and need to file with the IRS, you need an ITIN, not the Canadian ITN. The Canadian ITN is what a US resident would get to file Canadian taxes. They are mirror images, not interchangeable.
W-7 reason a through h, decision tree
Form W-7 has a single box at the top where you tick exactly one reason. The reason determines which extra forms must be attached. Get this wrong and the application bounces back unprocessed.
| Reason | When it applies (Canadian context) | Required attachment |
|---|---|---|
| a | Treaty benefit claim | Form 8233 or W-8BEN with treaty article cited |
| b | Filing US tax return as nonresident | Form 1040-NR |
| c | US resident filing US tax return | Rare for Canadians, only if substantial presence |
| d | Dependent of US person | Rare for Canadians |
| e | Spouse of US citizen or resident | Marriage cert + spouse's SSN |
| f | Nonresident alien student, professor, researcher | F-1, J-1, M-1 visa documentation |
| g | Dependent or spouse of nonresident alien holding US visa | Visa documentation |
| h | Other, including Exception 1(d) for foreign-owned SMLLC 5472 filers | Pro-forma 1120 with Form 5472 attached |
Most Canadians fall into a, b, or h. Reason h with Exception 1(d) is the path for foreign-owned single-member LLC owners who need to file 5472 but have no other US filing obligation.
Submission routes from Canada, and why TAC is not on the list
Articles on this topic often list three routes, mail, Certified Acceptance Agent, and IRS Taxpayer Assistance Center. The IRS does not operate any TAC location inside Canada. Crossing into Detroit, Buffalo, or Niagara Falls to use a US TAC is technically possible, but it is not a Canadian route.
Real options for someone in Canada:
| Route | Cost | Time | Risk |
|---|---|---|---|
| Mail to Austin TX | Free, plus courier fees | Off-season 7-11 weeks, peak season 11-17 weeks | Original passport sent overseas |
| CAA in Canada | Around $200-400 USD | Same processing time at IRS, but documents stay in Canada | Lower rejection risk, CAA reviews W-7 first |
| Certified copy from Canadian passport office | Around $45 CAD | Adds 2-4 weeks before mailing | Some CAA accept it, IRS prefers original |
The Austin mail route requires sending your original passport unless you have a certified copy from the issuing agency. For most Canadians, the Canadian passport office is the only acceptable issuer. A notarized copy from a lawyer or commissioner of oaths is not accepted by the IRS for ITIN purposes.
A CAA in Canada, typically a cross-border accountant in Toronto, Vancouver, or Calgary, can verify your passport in person and forward the application without your document leaving the country. This is the route we recommend when the timeline matters.
Form 5472 SMLLC timeline, when you actually need ITIN ready
A common mistake among Canadian LLC owners is rushing the ITIN application at formation. The deadline that matters is the first Form 5472 due date.
Calendar-year LLC formed in March of year 1:
| Milestone | Date | ITIN needed? |
|---|---|---|
| LLC formation | March, year 1 | No |
| First reportable transaction (e.g., capital contribution) | March, year 1 | No, but starts the clock |
| First 5472 due (1120 attachment) | April 15, year 2 | Yes, ITIN must be on 1120 line "Identifying number" |
| Form 7004 extension grants 6 more months | October 15, year 2 | Yes, by extended deadline |
If you start the ITIN application by January of year 2, off-season processing usually returns the number before the April 15 deadline. Start later, and you risk filing 5472 with "Applied For" in the ITIN field, which the IRS sometimes accepts and sometimes rejects.
There is no penalty for not having ITIN at formation. The penalty is for missing the 5472 itself, $25,000 minimum.
Renewal, expiration, and what happens after rejection
ITINs expire if not used on a US tax return for three consecutive years. If your last filing was in 2022 and you have not filed since, the ITIN is presumed inactive starting January 2026.
Renewal uses the same Form W-7, but you tick the Renew box at the top and submit only proof of identity, no tax return required. Processing time is similar to a new application.
If your ITIN is rejected, the IRS sends Notice CP567 with a reason code. Common rejection reasons for Canadians:
- Notarized copy of passport instead of certified copy from the issuing agency
- Form 1040-NR not attached when reason b was ticked
- W-7 reason h ticked without pro-forma 1120 + 5472 attached
- Mismatch between name on W-7 and name on passport, including hyphenation
A rejection does not penalize you. You re-submit with corrections. Most rejections in cross-border practice are paperwork formatting, not eligibility.
What ITIN does NOT do
The credit-card-churning corner of the Canadian internet has spread some half-truths about ITIN. To be clear:
- ITIN does not authorize you to work in the United States. That requires SSN with work authorization.
- ITIN does not make you eligible for Social Security benefits or the Earned Income Credit.
- ITIN does not open every US bank account. Most major banks still require SSN, US address, or in-person identity verification. Some neobanks accept ITIN.
- ITIN does not replace SSN for credit-bureau identity. Some lenders accept ITIN, most major issuers do not for prime cards.
If you have read elsewhere that "ITIN gets you US credit cards," that is true for a narrow set of issuers and not a general rule. We do not recommend applying for ITIN purely for credit purposes.
Frequently asked questions
How long does ITIN take for a Canadian? Off-season, mid-May through November, is 7-11 weeks. Peak filing season, January through April, is 11-17 weeks. Add 2-4 weeks if you are getting a certified passport copy from Passport Canada.
Can I apply for ITIN without filing a US tax return? Only under specific exceptions. Reason h with Exception 1(d), foreign-owned SMLLC 5472 filer, is the most common standalone path for Canadians. All other reasons require a US tax return attached.
Where do I send the W-7 from Canada? Mail to Internal Revenue Service, Austin, TX 73301-0057, USA. Or hand it to a CAA in Canada, who forwards it through their own channel. The address is in IRS instructions for Form W-7.