diff --git a/CHANGELOG.md b/CHANGELOG.md
index 51c71b0f5b..77c8871d4f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,8 @@
 
 #### Upcoming Changes
 
+* perf: Pre-allocate collections during program deserialization [#2300](https://github.com/lambdaclass/cairo-vm/pull/2300)
+
 * chore: Remove old compare-benchmarks Makefile command [#2307](https://github.com/lambdaclass/cairo-vm/pull/2307)
 
 * chore: Update iai-callgrind from 0.3.1 to 0.14.0 [#2311](https://github.com/lambdaclass/cairo-vm/pull/2311)
diff --git a/vm/src/serde/deserialize_program.rs b/vm/src/serde/deserialize_program.rs
index 2c483da77d..a45d24fb01 100644
--- a/vm/src/serde/deserialize_program.rs
+++ b/vm/src/serde/deserialize_program.rs
@@ -341,11 +341,12 @@ impl<'de> de::Visitor<'de> for MaybeRelocatableVisitor {
     where
         A: SeqAccess<'de>,
     {
-        let mut data: Vec<MaybeRelocatable> = vec![];
+        let mut data: Vec<MaybeRelocatable> =
+            Vec::with_capacity(seq.size_hint().unwrap_or_default());
 
         while let Some(value) = seq.next_element::<String>()? {
             // Add padding if necessary
-            let value = deserialize_utils::maybe_add_padding(value.to_string());
+            let value = deserialize_utils::maybe_add_padding(value);
             data.push(MaybeRelocatable::Int(
                 Felt252::from_hex(&value).map_err(de::Error::custom)?,
             ));
@@ -367,7 +368,8 @@ impl<'de> de::Visitor<'de> for ReferenceIdsVisitor {
     where
         A: MapAccess<'de>,
     {
-        let mut data: HashMap<String, usize> = HashMap::new();
+        let mut data: HashMap<String, usize> =
+            HashMap::with_capacity(map.size_hint().unwrap_or_default());
 
         while let Some((key, value)) = map.next_entry::<String, usize>()? {
             data.insert(key, value);