A job offer letter is a document that a Canadian employer gives you (as a temporary worker). It explains the details of your job.You need to ask a Texas lawyer. Learn what to include in a job offer letter and use our ready made template. The following is a TN visa sample letter for organizations wishing to hire Mexican or Canadian citizens. An Employment Offer Letter provides the employer with an opportunity to formally make an employment offer to an employee in a clear and concise fashion. The nonimmigrant USMCA Professional (TN) visa allows eligible citizens of Canada and Mexico to work in the United States as USMCA professionals. A sample letter offering a job contingent upon the results of a background check or other criteria. Once you have one of these numbers, you can apply to get, extend or modify a work permit. In most cases, the employer must send you: the written job offer and a Labour Market Impact Assessment (LMIA) number when applying abroad.