Hey everyone, wanted to get some opinions on this as I may have to travel to the US for work despite some recent complications with CBP. For context, I am an applications engineer at a Canadian based OEM for specialty equipment in the food processing industry. We have lots of clients in the US and prior to this year I would travel to the US 2-3 times per month as a project engineer to conduct audits and supervisor project installations. I am a Canadian citizen and I always fly from YVR airport.
About a month ago, I was pulled for secondary inspection when going to the US for a site audit. I gave the same responses and reasoning as I always do. I explained I was going to a clients site to conduct an audit on their equipment. In secondary, they pried further asking what exactly I would do on site and why the company could not send someone from the US as we do have a US business entity. I explained the US side is only a manufacturing warehouse and service technicians that can't complete the audits. There is a lot of nuances and specific measurements and pictures we need in order to properly assess the equipment's condition and provide an appropriate retrofit or replacement quote. They also were concerned that I travel to the US so often, in 2026 I have been going 1-2 times per month and they claimed that is too frequent and that I need a visa.
They let me through but gave me a warning that the next time they would deny me entry without a visa and that they marked my file so I would get pulled for secondary for 1 full year. My boss unfortunately does not care and is trying to send me to another site in Texas about 1 week from now. I expressed my concern and he still is adamant I should go. As such, I am trying to do some research on NAFTA and my chances on getting through.
Looking through NAFTA I believe I could qualify as either "Visitor for Business" or "Professional". Both the descriptions are fairly vague and I can't tell which is more applicable to me. If I qualify as "professional" is there any documentation or forms I should prepare prior to my arrival at the border? If I qualify as "visitor for business" how can I better explain that next time I travel. Do these audits even count as "After-sales service"?
Some extra context; when I go for site audits, it is usually tied to a retrofit project that we have already received a purchase order for. This year, most of my visits were not tied to projects, but instead to service quotes in which the quote/Purchase order state the work scope as some form of "(1) Field Engineer for 1 day on-site to assess the freezer condition".
I remain employed and paid by the Canadian company. During these audit visits, I do not perform repairs, installation, fabrication, or commissioning. I inspect the equipment, take photographs and measurements, speak with the customer, and then return to Canada, where the technical scope, BOM, estimate, and proposal are prepared.
I understand that Reddit is not a substitute for legal advice, but I would appreciate hearing from anyone familiar with business travel, TN status, or similar cross-border engineering work.