I have worked for three employers in 2017 and thus have three T4 forms, do I make three separate tax returns or collate all three together and file the one return?

You will do 1 return only enter one T4 at a time. Once, one is entered on the bottom it will say " Add another T4" click on that to complete the next one and so on till you have all 3 entered then you will click on DONE entering T4's  and continue.

There is no "add another T4" option that I can see. The field only allows for the uploading of one T4. I have to upload additional T4s under "other docs", which is fine, but I'm puzzled by the fact that the Employment Income field only allows the uploading of a single T4, as if no one ever works at more than one place per year. Every year, I have at least two T4 slips, and sometimes three. It doesn't make sense that the ability to upload more than one T4 has been taken away. 

Please see the image below and follow the steps to add more T4 information slips in your return.

 

 

When you are done adding all your T4 slips, you will then click on Done With T4 Slips.

 

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