How to protect your cheques in Canada

Not how to protect your cheques physically - that's up to you and your martial arts training.

I mean how to ensure your cheques are deposited to the account of your choosing.  Because even though you write on your cheques who the payee ought to be, it can be signed off to a third party to be cashed or deposited.

Other places in the world use markings to "cross" the cheque to ensure it is deposited to a bank account only, and not cashed (literally exchanged for cash).  In other places, you may write "non-negotiable" to ensure it is deposited or cashed only by the person named on the front as payee, and no one else.

But Canada and the USA does this differently.  USA should be similar (but you should check for yourself) to Canada, but the following is Canada specific:

Write "For deposit only to account of payee" on the back of the cheque to ensure that the cheque can only be deposited (not cashed) and to the named payee only (and can't be negotiated --- signed --- away to a third party) [1, 2].

[1] Added Protection when paying by Cheque --- Financial Consumer Agency of Canada
[2] Cheques - What You Need to Know --- Canadian Bankers Association