Do you need working papers to work in Toronto if are a US citizen and it is only 6 week job?

As a US citizen, you do not need a work permit to work in Canada. However, you may need to obtain a work permit if your job will last longer than six months.

For a job lasting less than six weeks, you can enter Canada as a visitor and work without a work permit. You will need to present your passport and proof of your employment at the port of entry.

If you are planning to stay in Canada for more than six weeks, you will need to apply for a work permit. The process for obtaining a work permit can be complex and time-consuming, so it is important to start early.

You can find more information about working in Canada on the website of the Canadian government.