diff --git a/x-pack/plugin/esql-core/src/main/java/org/elasticsearch/xpack/esql/core/util/CollectionUtils.java b/x-pack/plugin/esql-core/src/main/java/org/elasticsearch/xpack/esql/core/util/CollectionUtils.java
index 8f868230fb19..ce0540687121 100644
--- a/x-pack/plugin/esql-core/src/main/java/org/elasticsearch/xpack/esql/core/util/CollectionUtils.java
+++ b/x-pack/plugin/esql-core/src/main/java/org/elasticsearch/xpack/esql/core/util/CollectionUtils.java
@@ -69,13 +69,6 @@ public static <T> List<T> combine(Collection<? extends T> left, T... entries) {
         return list;
     }
 
-    public static int mapSize(int size) {
-        if (size < 2) {
-            return size + 1;
-        }
-        return (int) (size / 0.75f + 1f);
-    }
-
     @SafeVarargs
     @SuppressWarnings("varargs")
     public static <T> List<T> nullSafeList(T... entries) {