“I have a US job offer and my support letter is being prepared, but my employer needs an SSN for a background check before I can start. Since I need my TN visa to get an SSN, and I can only enter the US up to 10 days before my start date, can I fly to the US to get my TN, apply for the SSN, and then return to Canada to wait for the background check and serve my 30-day notice period at my current job?”
You do not necessarily need the physical SSN card—or even the assigned number—to satisfy Form I-9 and begin working after you have applied, provided you have acceptable I-9 documents. That gives your employer a cleaner option, although its background-check policy may still delay your start.
You have two workable sequences, but neither lets you use an inaccurate start date to obtain TN admission more than 10 days before the genuine validity period.
Complete your Canadian notice period, then seek TN admission no more than 10 days before the genuine TN validity date. After admission, apply for the SSN; if the employer’s only concern is Form I-9 or , USCIS says you may begin work while awaiting the number when you have acceptable I-9 documents, leaving the SSN field blank until it arrives (8 CFR 214.1(l)(1); Form I-9 Instructions, pp. 2 and 7).
You may seek TN admission within the permitted window, complete the in-person SSN application, return to Canada, and later seek readmission for the same job. The later admission may cover the remainder of the unexpired without a new support letter or fee only while the employer and professional activities remain unchanged (8 CFR 214.6(g)(1)); SSA processing after departure has no published guarantee in the cited materials.
Do not place an earlier date in the TN letter merely to fit the SSN trip if everyone already knows the genuine TN validity period begins later. A willful false statement relevant to eligibility for admission can be a (USCIS Policy Manual, Vol. 8, Pt. J, Ch. 3).
As a Canadian citizen, you normally seek directly from CBP rather than obtaining a TN visa stamp at a U.S. consulate (USCIS TN USMCA Professionals).
These steps keep your dates truthful, complete the SSN application correctly, and preserve the regulatory route for TN readmission.
Before finalizing the support letter
Set the genuine TN validity and work dates
If your genuine U.S. validity date follows the 30-day notice period, plan the first TN entry for no earlier than 10 days before that date. Separately, give HR the current Form I-9 rule: after you apply for an SSN, acceptable identity and work-authorization documents allow work to begin while the SSN field remains blank; the employer can update it after assignment.
Requirements
No more than 10 days before genuine TN validity
Seek TN admission from CBP
As a Canadian citizen, present the TN application directly to CBP at a designated port of entry or pre-clearance/pre-flight inspection station; no consular TN visa application is normally required. CBP determines eligibility, and you cannot perform the TN work until the authorized validity period begins.
Requirements
Immediately after admission
Keep the TN Form I-94 record
Keep the confirming TN admission. SSA uses a TN I-94 as employment-authorization evidence, and the later-readmission rule depends on that I-94 remaining unexpired.
Requirements
After TN admission
Complete the original SSN application
SSA recommends waiting 10 days after arrival to make DHS verification easier, although it describes this as a recommendation. Start online and complete the process at a Social Security office or Card Center within 45 days; call 1-800-772-1213 (TTY 1-800-325-0778) for the required appointment. The application is free, and photocopies or notarized copies are not accepted.
Requirements
Before returning to Canada
Finish the SSA visit before departing
Complete the in-person document review rather than leaving with only an online application. Form SS-5 includes a State/Foreign Country mailing field, but SSA only says it will mail the card after it has all information and verifies the documents; the cited SSA rules do not promise that post-departure verification will finish on a fixed schedule.
Requirements
After the background check and notice period
Seek TN readmission for the same job
Return and seek TN readmission under 8 CFR 214.6(g)(1). The regulation permits readmission for the remainder of the I-94 period without the original support letter or supporting documents and without the prescribed readmission fee when the employer and activities are unchanged and the I-94 has not expired.
Requirements
By your first workday
Complete Form I-9 and update the SSN later
Complete and sign Form I-9 Section 1 no later than your first day of paid work; the employer completes Section 2 within three business days. While the SSN is pending, leave its field blank, then enter the number, initial, and date the update after receipt. The employer must ultimately use the SSN for Form W-2 and cannot substitute an ITIN.
Requirements
You are not the first to go through this. Here is how it went for others who asked the same thing.
u/Snail-eggr/tnvisaMar 9, 2026
This answer is grounded in the current eCFR, USCIS, SSA, IRS, and FTC materials listed below.
8 CFR 214.1(l)(1)
TN workers may be admitted up to 10 days before the authorized validity period but ordinarily cannot work during those extra days.
(l)(1)
( 1 ) An alien admissible in E-1, E-2, E-3, H-1B, L-1, or TN classification and his or her dependents may be admitted to the United States or otherwise provided such status for the validity period of the petition, or for a validity period otherwise authorized for the E-1, E-2, E-3, and TN classifications, plus an additional period of up to 10 days before the validity period begins and 10 days after the validity period ends. Unless authorized under 8 CFR 274a.12 , the alien may not work except during the validity period.
8 CFR 214.6(g)(1)
Temporary travel does not necessarily require a new TN application when the original I-94 remains valid and the job is unchanged.
(g)(1)
An alien may be readmitted to the United States in TN classification for the remainder of the authorized period of TN admission on Form I-94 (see § 1.4 ), without presentation of the letter or supporting documentation described in paragraph (d)(3) of this section, and without the prescribed fee set forth in 8 CFR 106.2 , provided that the original intended professional activities and employer(s) have not changed, and the Form I-94 has not expired.
USCIS TN USMCA Professionals
A Canadian ordinarily establishes TN eligibility directly with CBP using proof of citizenship, the employer letter, and qualifying credentials.
Canadian Citizens
If you are a Canadian citizen residing outside the United States, you are not required to apply for a TN visa at a U.S. consulate. You may establish eligibility for TN classification at the time you seek admission to the United States by presenting required documentation to a U.S. Customs and Border Protection (CBP) officer at certain CBP-designated U.S. ports of entry or at a designated pre-clearance/pre-flight inspection station. You must provide the following documentation to the CBP officer: Proof of Canadian citizenship; Letter from your prospective employer detailing items such as the professional capacity in which you will work in the United States, the purpose of your employment, your length of stay, and your educational qualifications; and Credentials evaluation (if applicable), together with any applicable fees.
SSA POMS RM 10211.420
SSA treats the TN class of admission shown on Form I-94 as employment-authorized status for SSN purposes.
A–B, Class of Admission table
The alien's I-94 showing one of the following COAs has employment authorization unless otherwise noted. Form I-94 will not have the DHS employment authorization stamp and the alien may not have an EAD. |TN |Professional businessperson from Canada or Mexico, North American Free Trade Agreement (NAFTA). |
SSA Publication 05-10096
SSA recommends waiting 10 days after entry and requires completion of the online-started application at an SSA office within 45 days.
Applying in the United States
If you are unable or choose not to apply for an SSN using one of the methods above, we recommend you wait 10 days after arriving in the United States to apply for an SSN. To complete the application process, you must visit your local Social Security office or Card Center with the required documents within 45 days of starting the process. We will mail your SSN card as soon as we have all your information and have verified your documents with the issuing offices.
Form SS-5 (12-2024)
An original SSN application requires original or certified evidence of age, identity, and current work-authorized immigration status, plus a usable mailing address.
Evidence and Item 16
To apply for an original card, you must provide at least two documents to prove age, identity, and U.S. citizenship or current lawful, work-authorized immigration status. If you are not a U.S. citizen, we must see your current U.S. immigration document(s) and your foreign passport with biographical information or photograph. Show an address where you can receive your card 7 to 14 days from now.
Form I-9 Instructions (01/20/25)
A worker who has applied for an SSN may start work with acceptable I-9 documents and add the SSN after receiving it.
Pages 2 and 7
Providing your 9-digit Social Security number in the Social Security number field is voluntary, unless your employer participates in E-Verify. If you can present acceptable identity and employment authorization documentation to complete Form I-9, you may begin working while waiting to receive your Social Security number. If you have applied for, but have not yet received, your Social Security number, you should leave the field blank until you receive the number. Update this field once you receive it, and initial and date the notation.
IRS Hiring Employees
The employer ultimately needs the employee’s SSN for Form W-2, and an ITIN cannot replace it.
Employee’s Social Security number
You are required to get each employee's name and Social Security number (SSN) and to enter them on Form W-2 (this requirement also applies to resident and nonresident alien employees). Do not accept an ITIN in place of an SSN for employee identification or for work.
USCIS Policy Manual Vol. 8 Pt. J Ch. 3
A knowingly false start date can create serious immigration risk if it is relevant to eligibility for admission.
Materiality
A false representation only renders an alien inadmissible if it is material. A “material” misrepresentation is a false representation concerning a fact that is relevant to the alien’s eligibility for an immigration benefit.
FTC FCRA Employment Guidance
Federal consumer-report rules require notice and written permission for a third-party employment background check; they are separate from I-9 rules.
Before You Get Background Information
Tell the applicant or employee you might use the information for decisions about his or her employment. This notice must be in writing and in a stand-alone format. The notice can’t be in an employment application. Get the applicant’s or employee’s written permission to do the background check.
These are the official rules and forms as published on the cited dates; immigration, SSA, and employment-verification rules can change.
This is general information about official processes, not legal advice; SettleKit is not a law firm.
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