diff --git a/src/llama-vocab.cpp b/src/llama-vocab.cpp
index 29e31cecd1565..a73c4c448ba53 100644
--- a/src/llama-vocab.cpp
+++ b/src/llama-vocab.cpp
@@ -1281,6 +1281,7 @@ struct llm_tokenizer_plamo2 : llm_tokenizer {
 
         // Build suffix list in lexicographical order of reversed strings
         std::vector<std::string> suffixes;
+        suffixes.reserve(suffix_to_score.size() + 1);
         for (const auto & pair : suffix_to_score) {
             suffixes.push_back(pair.first);
         }