Even if salmon is frozen or smoked, it eventually goes bad. Various preservation methods give it a variety of shelf lives, but the printed date on the package gives an idea as to when salmon needs to go into the trash.
Salmon should be eaten or frozen as soon as possible. It lasts in the refrigerator for a day or two past the printed date. Smoked salmon from a store and kept in a refrigerator is likely to be good for a week past the printed date. Frozen salmon that is thawed does not spoil for four or five days. Canned salmon is good for six to eight months. Salmon kept in the freezer remains usable for up to nine months.