diff --git a/crates/oxc_parser/src/diagnostics.rs b/crates/oxc_parser/src/diagnostics.rs
index 44beefcbd8517..0cd7616f02e51 100644
--- a/crates/oxc_parser/src/diagnostics.rs
+++ b/crates/oxc_parser/src/diagnostics.rs
@@ -435,16 +435,6 @@ pub fn jsx_expressions_may_not_use_the_comma_operator(span: Span) -> OxcDiagnost
         .with_label(span)
 }
 
-#[cold]
-pub fn line_terminator_before_using_declaration(span: Span) -> OxcDiagnostic {
-    OxcDiagnostic::error("Line terminator not permitted before using declaration.").with_label(span)
-}
-
-#[cold]
-pub fn await_in_using_declaration(span: Span) -> OxcDiagnostic {
-    OxcDiagnostic::error("Await is not allowed in using declarations.").with_label(span)
-}
-
 #[cold]
 pub fn invalid_identifier_in_using_declaration(span: Span) -> OxcDiagnostic {
     OxcDiagnostic::error("Using declarations may not have binding patterns.").with_label(span)
diff --git a/crates/oxc_parser/src/js/declaration.rs b/crates/oxc_parser/src/js/declaration.rs
index d2503886e4e51..5eb8cd6015bfc 100644
--- a/crates/oxc_parser/src/js/declaration.rs
+++ b/crates/oxc_parser/src/js/declaration.rs
@@ -143,19 +143,6 @@ impl<'a> ParserImpl<'a> {
 
         self.expect(Kind::Using)?;
 
-        // `[no LineTerminator here]`
-        if self.cur_token().is_on_new_line {
-            self.error(diagnostics::line_terminator_before_using_declaration(
-                self.cur_token().span(),
-            ));
-        }
-
-        // [lookahead ≠ await]
-        if self.cur_kind() == Kind::Await {
-            self.error(diagnostics::await_in_using_declaration(self.cur_token().span()));
-            self.eat(Kind::Await);
-        }
-
         // BindingList[?In, ?Yield, ?Await, ~Pattern]
         let mut declarations: oxc_allocator::Vec<'_, VariableDeclarator<'_>> = self.ast.vec();
         loop {
diff --git a/crates/oxc_parser/src/js/statement.rs b/crates/oxc_parser/src/js/statement.rs
index e0261b9abceaa..5e53f12ec8678 100644
--- a/crates/oxc_parser/src/js/statement.rs
+++ b/crates/oxc_parser/src/js/statement.rs
@@ -114,20 +114,42 @@ impl<'a> ParserImpl<'a> {
             // Fast path
             Kind::Function => self.parse_function_declaration(stmt_ctx),
             Kind::Let if !self.cur_token().escaped() => self.parse_let(stmt_ctx),
+            // Peek tokens
+            Kind::Async
+                if {
+                    let peek_token = self.peek_token();
+                    peek_token.kind == Kind::Function && !peek_token.is_on_new_line
+                } =>
+            {
+                self.parse_function_declaration(stmt_ctx)
+            }
             Kind::Import if !matches!(self.peek_kind(), Kind::Dot | Kind::LParen) => {
                 self.parse_import_declaration()
             }
-            Kind::Const if !(self.is_ts && self.is_at_enum_declaration()) => {
+            Kind::Const if !(self.is_ts && self.peek_at(Kind::Enum)) => {
                 self.parse_variable_statement(stmt_ctx)
             }
-            Kind::Await
-                if self.peek_kind() == Kind::Using && self.nth_kind(2).is_binding_identifier() =>
+            Kind::Using
+                if {
+                    let peek_token = self.peek_token();
+                    peek_token.kind.is_binding_identifier() && !peek_token.is_on_new_line
+                } =>
             {
                 self.parse_using_statement()
             }
-            Kind::Using if self.peek_kind().is_binding_identifier() => self.parse_using_statement(),
-            Kind::Async if self.peek_at(Kind::Function) && !self.peek_token().is_on_new_line => {
-                self.parse_function_declaration(stmt_ctx)
+            // Peek 2 tokens
+            Kind::Await
+                if {
+                    let peek_token = self.peek_token();
+                    if peek_token.kind == Kind::Using && !peek_token.is_on_new_line {
+                        let peek2_token = self.nth(2);
+                        peek2_token.kind.is_binding_identifier() && !peek2_token.is_on_new_line
+                    } else {
+                        false
+                    }
+                } =>
+            {
+                self.parse_using_statement()
             }
             _ if self.is_ts && self.at_start_of_ts_declaration() => {
                 self.parse_ts_declaration_statement(start_span)
diff --git a/crates/oxc_parser/src/ts/statement.rs b/crates/oxc_parser/src/ts/statement.rs
index 5799fcf5c46f3..9466f8301bbb5 100644
--- a/crates/oxc_parser/src/ts/statement.rs
+++ b/crates/oxc_parser/src/ts/statement.rs
@@ -12,11 +12,6 @@ use crate::{
 
 impl<'a> ParserImpl<'a> {
     /* ------------------- Enum ------------------ */
-
-    pub(crate) fn is_at_enum_declaration(&mut self) -> bool {
-        self.at(Kind::Enum) || (self.at(Kind::Const) && self.peek_at(Kind::Enum))
-    }
-
     /// `https://www.typescriptlang.org/docs/handbook/enums.html`
     pub(crate) fn parse_ts_enum_declaration(
         &mut self,
diff --git a/tasks/coverage/misc/pass/oxc-10503.ts b/tasks/coverage/misc/pass/oxc-10503.ts
new file mode 100644
index 0000000000000..8c0bbd2d6e7f6
--- /dev/null
+++ b/tasks/coverage/misc/pass/oxc-10503.ts
@@ -0,0 +1,5 @@
+using
+foo = bar();
+
+await using
+foo = bar();
diff --git a/tasks/coverage/snapshots/codegen_misc.snap b/tasks/coverage/snapshots/codegen_misc.snap
index 614cc1865e797..43f781ca30240 100644
--- a/tasks/coverage/snapshots/codegen_misc.snap
+++ b/tasks/coverage/snapshots/codegen_misc.snap
@@ -1,3 +1,3 @@
 codegen_misc Summary:
-AST Parsed     : 34/34 (100.00%)
-Positive Passed: 34/34 (100.00%)
+AST Parsed     : 35/35 (100.00%)
+Positive Passed: 35/35 (100.00%)
diff --git a/tasks/coverage/snapshots/parser_misc.snap b/tasks/coverage/snapshots/parser_misc.snap
index ecf1285422606..f7fd7f139096e 100644
--- a/tasks/coverage/snapshots/parser_misc.snap
+++ b/tasks/coverage/snapshots/parser_misc.snap
@@ -1,6 +1,6 @@
 parser_misc Summary:
-AST Parsed     : 34/34 (100.00%)
-Positive Passed: 34/34 (100.00%)
+AST Parsed     : 35/35 (100.00%)
+Positive Passed: 35/35 (100.00%)
 Negative Passed: 31/31 (100.00%)
 
   × Identifier `b` has already been declared
diff --git a/tasks/coverage/snapshots/semantic_misc.snap b/tasks/coverage/snapshots/semantic_misc.snap
index 806c49746f870..bc81df867f7e8 100644
--- a/tasks/coverage/snapshots/semantic_misc.snap
+++ b/tasks/coverage/snapshots/semantic_misc.snap
@@ -1,6 +1,6 @@
 semantic_misc Summary:
-AST Parsed     : 34/34 (100.00%)
-Positive Passed: 19/34 (55.88%)
+AST Parsed     : 35/35 (100.00%)
+Positive Passed: 20/35 (57.14%)
 tasks/coverage/misc/pass/oxc-1288.ts
 semantic error: Bindings mismatch:
 after transform: ScopeId(0): ["from"]
diff --git a/tasks/coverage/snapshots/transformer_misc.snap b/tasks/coverage/snapshots/transformer_misc.snap
index b17f9c51ca5cc..c9b0be2ed71a2 100644
--- a/tasks/coverage/snapshots/transformer_misc.snap
+++ b/tasks/coverage/snapshots/transformer_misc.snap
@@ -1,3 +1,3 @@
 transformer_misc Summary:
-AST Parsed     : 34/34 (100.00%)
-Positive Passed: 34/34 (100.00%)
+AST Parsed     : 35/35 (100.00%)
+Positive Passed: 35/35 (100.00%)