Tobacco product limits are listed in the table on this page. If you are 18 years of age or over, you are allowed to bring in all of the amounts listed in the table into Canada free of duty and taxes within your personal exemption.
If you include cigarettes, tobacco sticks or manufactured tobacco in your personal exemption, a partial exemption only may apply. You will have to pay a special duty on these products unless they have an excise stamp "DUTY PAID CANADA DROIT ACQUITTÉ." You will find Canadian-made products sold at duty-free shops marked this way. You can speed up your clearance by having your tobacco products available for inspection when you arrive.
For further details on bringing back tobacco products, consult I Declare - Tobacco products.