diff --git a/dialects/postgresql/src/main/kotlin/app/cash/sqldelight/dialects/postgresql/grammar/PostgreSql.bnf b/dialects/postgresql/src/main/kotlin/app/cash/sqldelight/dialects/postgresql/grammar/PostgreSql.bnf
index 6ec34c0a456..50f85881755 100644
--- a/dialects/postgresql/src/main/kotlin/app/cash/sqldelight/dialects/postgresql/grammar/PostgreSql.bnf
+++ b/dialects/postgresql/src/main/kotlin/app/cash/sqldelight/dialects/postgresql/grammar/PostgreSql.bnf
@@ -242,12 +242,14 @@ compound_select_stmt ::= [ {with_clause} ] {select_stmt}  ( {compound_operator}
   override = true
 }
 
-extension_expr ::= json_expression | boolean_literal {
+extension_expr ::= json_expression | boolean_literal | boolean_not_expression {
   extends = "com.alecstrong.sql.psi.core.psi.impl.SqlExtensionExprImpl"
   implements = "com.alecstrong.sql.psi.core.psi.SqlExtensionExpr"
   override = true
 }
 
+boolean_not_expression ::= NOT (boolean_literal | {column_name})
+
 boolean_literal ::= TRUE | FALSE
 
 json_expression ::= {column_name} ( jsona_binary_operator | jsonb_binary_operator ) <<expr '-1'>> {
diff --git a/dialects/postgresql/src/test/fixtures_postgresql/column_types/Sample.s b/dialects/postgresql/src/test/fixtures_postgresql/column_types/Sample.s
index 35f218ceca1..e9fa7af66be 100644
--- a/dialects/postgresql/src/test/fixtures_postgresql/column_types/Sample.s
+++ b/dialects/postgresql/src/test/fixtures_postgresql/column_types/Sample.s
@@ -62,3 +62,6 @@ CREATE TABLE all_types(
 
   some_int2_array INT2[]
 );
+
+SELECT * FROM all_types
+WHERE NOT some_boolean AND NOT some_bool = some_boolean AND NOT TRUE;