More information on US Business Visas for our clients
As part of our series on US Business Visas, discussed here and here, there is an exception to the rule that prohibits work in the US without a work permit. The general rule is that if you wish to work in the US, you require a US Work Permit such as a TN, E-2, or L-1 Visa. These Work Permits can be properly considered “business visas” but are more than that, in that, you can work directly in the US.
However, there are many Canadians entering the US as “business visitors” under B-1 status where they are not permitted to work in the US. Rather they can attend meetings or conferences, negotiate contracts, visit clients but are not able to directly work and earn an income while in the US. Under NAFTA, there is an exception to this rule of non-work for business visitors: the after-sales service provisions.
Generally, the after sales service provisions allow workers to enter the US to provide after-sales service work pursuant to a contract or warranty for goods manufactured outside of the US. After Sales Service Workers  are often called to the US to install software or equipment for goods purchased outside of the US. In order to qualify for this visa, you should have a copy of the sales agreement or contract that has the after sales service provision as part of the contract or an addendum to it. Obviously your credentials as an installer technician and proof of Canadian identity should be included.
Typically after sales service workers enter the US for short periods to do their work and then return. Multiple visits to the US may be required so it is important to carry with you all this documentation each time you travel to the US.