diff --git a/CHANGELOG b/CHANGELOG
index 671f2abe4..e85961b0a 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -9,6 +9,7 @@
  * Add a fourth `array $tests` argument to `Twig\Sandbox\SecurityPolicyInterface::checkSecurity()`
  * Throw a `SyntaxError` when an `extends`, `use`, or `macro` tag is not at the root of a template
  * Throw a `SyntaxError` when a macro is defined more than once in a template
+ * Throw a `SyntaxError` when calling a macro without parentheses
 
 # 4.0.0 alpha 1 (2026-05-17)
 
diff --git a/src/Node/Expression/MacroReferenceExpression.php b/src/Node/Expression/MacroReferenceExpression.php
index 546b0fb87..108c19325 100644
--- a/src/Node/Expression/MacroReferenceExpression.php
+++ b/src/Node/Expression/MacroReferenceExpression.php
@@ -12,6 +12,7 @@
 namespace Twig\Node\Expression;
 
 use Twig\Compiler;
+use Twig\Error\SyntaxError;
 use Twig\Node\CoercesChildrenToStringInterface;
 use Twig\Node\Expression\Variable\MacroVariable;
 
@@ -73,7 +74,7 @@ class MacroReferenceExpression extends AbstractExpression implements SupportDefi
     public function compile(Compiler $compiler): void
     {
         if (!$this->hasParentheses && !$this->definedTest) {
-            trigger_deprecation('twig/twig', '3.29', 'Omitting parentheses when calling a macro is deprecated and will throw a SyntaxError in Twig 4.0; add parentheses after the macro name in "%s" at line %d.', $this->getTemplateName(), $this->getTemplateLine());
+            throw new SyntaxError('Omitting parentheses when calling a macro is not allowed; add parentheses after the macro name.', $this->getTemplateLine(), $this->getSourceContext());
         }
 
         if ($this->hasNode('name')) {
diff --git a/tests/Fixtures/macros/call_without_parentheses.legacy.test b/tests/Fixtures/macros/call_without_parentheses.legacy.test
deleted file mode 100644
index bdb93d656..000000000
--- a/tests/Fixtures/macros/call_without_parentheses.legacy.test
+++ /dev/null
@@ -1,16 +0,0 @@
---TEST--
-Omitting parentheses when calling macros is deprecated
---DEPRECATION--
-Since twig/twig 3.29: Omitting parentheses when calling a macro is deprecated and will throw a SyntaxError in Twig 4.0; add parentheses after the macro name in "index.twig" at line 4.
-Since twig/twig 3.29: Omitting parentheses when calling a macro is deprecated and will throw a SyntaxError in Twig 4.0; add parentheses after the macro name in "index.twig" at line 5.
---TEMPLATE--
-{% import _self as macros %}
-{% set name = 'hello' %}
-{{ macros.hello }}
-{{ _self.(name) }}
-{% macro hello() %}Hello{% endmacro %}
---DATA--
-return []
---EXPECT--
-Hello
-Hello
diff --git a/tests/Fixtures/macros/call_without_parentheses.test b/tests/Fixtures/macros/call_without_parentheses.test
new file mode 100644
index 000000000..72e180437
--- /dev/null
+++ b/tests/Fixtures/macros/call_without_parentheses.test
@@ -0,0 +1,10 @@
+--TEST--
+Calling a macro without parentheses is forbidden
+--TEMPLATE--
+{% import _self as macros %}
+{{ macros.hello }}
+{% macro hello() %}Hello{% endmacro %}
+--DATA--
+return []
+--EXCEPTION--
+Twig\Error\SyntaxError: Omitting parentheses when calling a macro is not allowed; add parentheses after the macro name in "index.twig" at line 3.
diff --git a/tests/Fixtures/macros/dynamic_call_without_parentheses.test b/tests/Fixtures/macros/dynamic_call_without_parentheses.test
new file mode 100644
index 000000000..3c08a1b6b
--- /dev/null
+++ b/tests/Fixtures/macros/dynamic_call_without_parentheses.test
@@ -0,0 +1,11 @@
+--TEST--
+Calling a dynamic macro without parentheses is forbidden
+--TEMPLATE--
+{% import _self as macros %}
+{% set name = 'hello' %}
+{{ macros.(name) }}
+{% macro hello() %}Hello{% endmacro %}
+--DATA--
+return []
+--EXCEPTION--
+Twig\Error\SyntaxError: Omitting parentheses when calling a macro is not allowed; add parentheses after the macro name in "index.twig" at line 4.