IN THIS GUIDE · Explaining an employer’s legal address and the actual professional worksite
Start with the TN eligibility and application overview
Identify the legal party
Ask for the legal name of the entity offering the professional engagement and its correspondence address. Confirm how that name appears on the contract. A building sign, recruiter’s brand or payroll processor should not be substituted for the actual party without explaining its role. Request the signed offer, the signer's title, and the entity's tax or registration record before drafting. The decision is whether the named company is truly responsible for the engagement or merely an intermediary.
List expected places of work
Describe where the duties will actually be performed and why each location is involved. Identify client sites and recurring travel without inventing locations not yet agreed. If the employer does not know a destination, disclose that uncertainty for review rather than inserting its headquarters as a placeholder. Keep a dated itinerary only for locations that are known. It helps distinguish an occasional visit from a recurring placement and prevents a broad travel phrase from concealing the expected work pattern.
Explain who directs the work at each site
A customer location may involve a contract between several parties. Describe who assigns duties, who pays and what services have been agreed. Let counsel assess the actual employment structure; do not assume every new address is a new employer or that one employer name covers every relationship. Hypothetical example: a geothermal survey company hires a Canadian geologist to interpret borehole data for two developers. The decision is whether the company, rather than either developer, directs the professional work; the service agreement and reporting instructions answer that question.
Set a change-reporting process
Ask the employer to report a changed site, client or employing entity before the affected work begins. The immigration consequences depend on the facts, not simply the distance moved. Keep the current description accurate and obtain advice on whether a change requires a further step. Before travel, compare the revised facts with the original support letter. A new client may be immaterial or may alter the practical arrangement; the signed documents, not an informal assurance, provide the record for that judgment.
Apply the temporary-work and credential boundaries
TN requires temporary activity in a listed USMCA profession and its particular qualifications for Canadian or Mexican citizens; Canadian permanent residence alone is insufficient. A port-of-entry application gives a same-day answer; a Form I-129 petition gives a written approval before travel and suits a file with a prior refusal, an experience-based credential or an ownership stake. Canadian citizens generally may apply for TN admission at a port of entry without a visa, or an eligible U.S. employer may file Form I-129 with USCIS; Mexican citizens generally require a TN visa before seeking admission. A first review should pair the offered duties with the exact profession listed in the USMCA schedule, then match each required credential to a primary record: final transcript, degree certificate, licence record, or credential evaluation where applicable.
Sources reviewed 2026-09-07. This guide covers a preparation focus; it is not an individual eligibility assessment.