diff --git a/CHANGELOG.md b/CHANGELOG.md
index 46d04b3471..4a67bc2166 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 - `tezos_data_encoding`: The `NomReader` trait is now explicitly
 parameterized by the lifetime of the input byte slice.
+- Altered hashes to implement `AsRef<[u8]>` instead of `AsRef<Vec<u8>>`.
 
 ### Deprecated
 
diff --git a/crypto/src/blake2b.rs b/crypto/src/blake2b.rs
index 1a3aea1f6e..c98b2c3df2 100644
--- a/crypto/src/blake2b.rs
+++ b/crypto/src/blake2b.rs
@@ -101,7 +101,7 @@ where
 // this implementation will calculate the same hash [5, 5] two times.
 pub fn merkle_tree<Leaf>(list: &[Leaf]) -> Result<Vec<u8>, Blake2bError>
 where
-    Leaf: AsRef<Vec<u8>>,
+    Leaf: AsRef<[u8]>,
 {
     use std::ops::{Index, RangeFrom, RangeTo};
 
@@ -156,7 +156,7 @@ where
         degree: u32,
     ) -> Result<Vec<u8>, Blake2bError>
     where
-        Leaf: AsRef<Vec<u8>>,
+        Leaf: AsRef<[u8]>,
     {
         match degree {
             0 => digest_256(list[0].as_ref()),
diff --git a/crypto/src/hash.rs b/crypto/src/hash.rs
index 3478e077cd..a6b42b5723 100644
--- a/crypto/src/hash.rs
+++ b/crypto/src/hash.rs
@@ -51,7 +51,7 @@ mod prefix_bytes {
 
 pub type Hash = Vec<u8>;
 
-pub trait HashTrait: Into<Hash> + AsRef<Hash> {
+pub trait HashTrait: Into<Hash> + AsRef<[u8]> {
     /// Returns this hash type.
     fn hash_type() -> HashType;
 
@@ -171,8 +171,8 @@ macro_rules! define_hash {
             }
         }
 
-        impl std::convert::AsRef<Hash> for $name {
-            fn as_ref(&self) -> &Hash {
+        impl std::convert::AsRef<[u8]> for $name {
+            fn as_ref(&self) -> &[u8] {
                 &self.0
             }
         }