diff --git a/src/Query/Postgresql/DateTrunc.php b/src/Query/Postgresql/DateTrunc.php
index 9ceefbf8..dadbccff 100644
--- a/src/Query/Postgresql/DateTrunc.php
+++ b/src/Query/Postgresql/DateTrunc.php
@@ -13,6 +13,8 @@ class DateTrunc extends FunctionNode
 
     public $fieldTimestamp = null;
 
+    public $fieldTimezone = null;
+
     public function parse(Parser $parser): void
     {
         $parser->match(Lexer::T_IDENTIFIER);
@@ -20,15 +22,27 @@ public function parse(Parser $parser): void
         $this->fieldText = $parser->ArithmeticPrimary();
         $parser->match(Lexer::T_COMMA);
         $this->fieldTimestamp = $parser->ArithmeticPrimary();
+        if ($parser->getLexer()->lookahead['type'] === Lexer::T_COMMA) {
+            $parser->match(Lexer::T_COMMA);
+            $this->fieldTimezone = $parser->ArithmeticPrimary();
+        }
         $parser->match(Lexer::T_CLOSE_PARENTHESIS);
     }
 
     public function getSql(SqlWalker $sqlWalker): string
     {
-        return sprintf(
-            'DATE_TRUNC(%s, %s)',
+        $sql = sprintf(
+            'DATE_TRUNC(%s, %s',
             $this->fieldText->dispatch($sqlWalker),
             $this->fieldTimestamp->dispatch($sqlWalker)
         );
+
+        if ($this->fieldTimezone !== null) {
+            $sql .= sprintf(', %s', $this->fieldTimezone->dispatch($sqlWalker));
+        }
+
+        $sql .= ')';
+
+        return $sql;
     }
 }