diff --git a/prism/templates/src/diagnostic.c.erb b/prism/templates/src/diagnostic.c.erb
index 5536b7b922..9406436c2b 100644
--- a/prism/templates/src/diagnostic.c.erb
+++ b/prism/templates/src/diagnostic.c.erb
@@ -212,7 +212,7 @@ static const pm_diagnostic_data_t diagnostic_messages[PM_DIAGNOSTIC_ID_MAX] = {
     [PM_ERR_HASH_TERM]                          = { "expected a `}` to close the hash literal", PM_ERROR_LEVEL_SYNTAX },
     [PM_ERR_HASH_VALUE]                         = { "expected a value in the hash literal", PM_ERROR_LEVEL_SYNTAX },
     [PM_ERR_HEREDOC_IDENTIFIER]                 = { "unterminated here document identifier", PM_ERROR_LEVEL_SYNTAX },
-    [PM_ERR_HEREDOC_TERM]                       = { "unterminated heredoc; can't find string \"%.*s\"", PM_ERROR_LEVEL_SYNTAX },
+    [PM_ERR_HEREDOC_TERM]                       = { "unterminated heredoc; can't find string \"%.*s\" anywhere before EOF", PM_ERROR_LEVEL_SYNTAX },
     [PM_ERR_INCOMPLETE_QUESTION_MARK]           = { "incomplete expression at `?`", PM_ERROR_LEVEL_SYNTAX },
     [PM_ERR_INCOMPLETE_VARIABLE_CLASS_3_3]      = { "`%.*s' is not allowed as a class variable name", PM_ERROR_LEVEL_SYNTAX },
     [PM_ERR_INCOMPLETE_VARIABLE_CLASS]          = { "'%.*s' is not allowed as a class variable name", PM_ERROR_LEVEL_SYNTAX },
diff --git a/test/prism/errors_test.rb b/test/prism/errors_test.rb
index 280bf63a24..db4d2af5e1 100644
--- a/test/prism/errors_test.rb
+++ b/test/prism/errors_test.rb
@@ -1241,7 +1241,7 @@ module Prism
       expected = CallNode(0, receiver, Location(), :foo, Location(), nil, nil, nil, nil)
 
       assert_errors expected, "<<~FOO.foo\n", [
-        ["unterminated heredoc; can't find string \"FOO\"", 3..6]
+        ["unterminated heredoc; can't find string \"FOO\" anywhere before EOF", 3..6]
       ]
     end