The TN visa has one decisive advantage over every other U.S. work visa category: the border crossing is the adjudication. No petition, no USCIS queue, no waiting months for approval. An engineer with a properly assembled packet can cross on a Tuesday and be on your jobsite Wednesday. Here's how to build that into your project schedule.
Why TN Is Different
Most U.S. work visa categories involve filing a petition with USCIS and waiting for a decision — weeks or months, depending on the category and processing load. H-1B requires an annual lottery. H-2B requires DOL certification before USCIS even sees the petition. O-1 requires extensive documentation of extraordinary ability.
TN skips all of that. Under USMCA, Mexican and Canadian professionals in qualifying occupations present their qualifications directly to a CBP (Customs and Border Protection) officer at a port of entry. The officer reviews the packet and makes a determination on the spot. If approved, the worker receives an I-94 record valid for up to three years — and can start work immediately.
This is the mechanism that makes TN a viable tool for project-based construction hiring. The timeline is 3–6 weeks, and most of that is on our side — preparing documents and coordinating the crossing. The border crossing itself is typically 30–60 minutes.
Week-by-Week Timeline
Weeks 1–2: Intake and Candidate Confirmation
The process starts with BuildCorridor receiving and confirming your role requirements. In this phase, we verify that the role qualifies as a TN occupation, confirm the candidate is a Mexican or Canadian citizen, and begin assembling the document package.
If you're doing direct hire, the candidate interview typically happens in this window as well. We coordinate scheduling, provide interview guidance, and confirm your intent to proceed.
Weeks 2–3: Document Preparation
The core of TN preparation is the employer support letter — a detailed document on company letterhead that describes the role, the qualifying TN occupation category, the candidate's credentials, the duration and location of employment, and the employer's business purpose. This is not a USCIS petition — it doesn't go to any government agency before the border crossing. But it must be precise: CBP officers look for specific language and consistent details.
The candidate assembles their supporting documents in parallel: engineering degree certificate (with official translation if needed), professional license (Cédula Profesional in Mexico), passport, and any prior work authorization records if re-entering TN status.
Weeks 3–4: Candidate Preparation and Interview
We conduct a pre-crossing preparation session with the candidate — reviewing what to expect at the border, how to respond to CBP officer questions, and what to do if asked for additional documentation. Most TN crossings are straightforward. The preparation is about removing unnecessary risk from what is already a quick process.
For direct hire placements, the formal interview with your team happens in this window if not already completed. We coordinate and prepare both parties.
Week 4–6: Border Crossing and Approval
The crossing is scheduled at a land port of entry or a U.S. preclearance airport. For Mexican citizens, common crossing points include Laredo-Colombia (TX), El Paso (TX), San Diego-Otay Mesa (CA), and Nogales (AZ). We recommend weekday morning crossings — traffic is lower and officer changeovers haven't happened yet.
The CBP officer reviews the packet, may ask questions about the role and the employer, and makes a determination. Approval rate for well-prepared TN packets is very high. The officer issues an I-94 record with a validity period (up to 3 years). The worker can drive to your jobsite the same day.
Total timeline: 3–6 weeks from first conversation to first day on site. Buffer toward 6 weeks if the candidate needs credential translation or if there's a multi-party interview process. Buffer toward 3 weeks for straightforward roles with candidates already in the pipeline.
How to Build TN Into Your Project Schedule
The most common scheduling mistake is treating cross-border hiring as an option of last resort — exhausting domestic recruiting first, then calling BuildCorridor with 3 weeks to mobilization. At that point, even TN's fast timeline becomes a problem.
Build the staffing decision point into your project schedule at bid or pre-construction, not after notice to proceed. The right question at pre-construction is: which roles on this project are unlikely to be filled domestically within my mobilization window? Start the cross-border process for those roles in parallel with domestic recruiting — not after it fails.
| Milestone | TN Visa | H-2B Visa |
|---|---|---|
| Decision to pursue | Week 0 | Week 0 |
| DOL certification filed | N/A | Week 1–2 |
| USCIS petition filed | N/A | Week 10–12 |
| Government approval | Same day at border | Week 18–24 |
| Worker on site | Week 4–6 | Week 18–26 |
| Premium processing available? | N/A (not needed) | Yes (adds $2,805; saves ~8 weeks on USCIS side) |
Risk Factors That Add Time
A well-prepared TN packet is approved at the border in the overwhelming majority of cases. The factors that cause delays or denials are largely controllable:
- Incomplete or inconsistent support letter: The employer letter must match the candidate's credentials precisely. Mismatches between the stated role, the TN occupation category, and the candidate's actual degree raise flags.
- Role doesn't clearly fit a TN category: Some job titles require careful framing. A "construction manager" may or may not qualify; a "civil engineer performing construction management functions" likely does. This is where attorney-reviewed letter language matters.
- Credential documentation gaps: Missing degree certificates, untranslated documents, or unlicensed professions in occupations that require licensure in Mexico.
- Port of entry selection: Some ports are faster than others for TN processing. Busy commercial crossings on Fridays can result in longer waits.
- Prior immigration issues: Any prior overstays, visa violations, or inadmissibility grounds require review before initiating the crossing.
TN Renewal: What Happens After 3 Years
TN status can be renewed indefinitely — there is no maximum period of authorized stay and no H-1B-style cap on renewals. Renewal can be done through a new border crossing (the same process as initial TN) or, for workers already in the U.S., through a USCIS petition (Form I-129) without requiring the worker to leave the country. We handle both approaches and coordinate renewal timing so there is no gap in work authorization.
For engineers you intend to keep permanently, TN is compatible with pursuing permanent residency through the employer sponsorship process. TN holders can pursue green card applications without abandoning TN status.
Ready to start the TN process for your open role?
Give us the role, the candidate's country of origin, and your target mobilization date. We'll confirm TN eligibility and give you a precise timeline within 24 hours.
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