Avoiding encryption in a deduplication vault. In one example embodiment, a method may include analyzing an allocated plain text block stored in the source storage to determine if the block is already stored in the deduplication storage, in response to the block not being stored, encrypting the allocated plain text block and analyzing the encrypted block to determine if the encrypted block is already stored in the deduplication storage, analyzing a second allocated plain text block stored in the source storage to determine if the block is already stored in the deduplication storage, in response to the block already being stored, avoiding encryption of the second allocated plain text block by not encrypting the second allocated plain text block and instead associating the location of the second allocated plain text block in the source storage with the location of the duplicate block already stored.