Can I freeze salsa?

Yes. However, freezing may degrade the texture of tomatoes, onions, peppers, and other high-moisture ingredients. This is because moisture freezes, expands, and bursts the cell walls of these ingredients. For this reason, picante and other puréed salsas will likely store better than the other types.
 
Store the salsa in an airtight plastic container or a sealable plastic bag. The higher you fill the bag or container, the less room there is for oxygen, the cause of freezer burn. Leave about an inch of head space in the container to accommodate the expansion that occurs in frozen foods.
 
Source(s):
University of Minnesota "Preserving Salsa"