diff --git a/src/solidlsp/language_servers/typescript_language_server.py b/src/solidlsp/language_servers/typescript_language_server.py
index 5b7ec4fe..ddf3f605 100644
--- a/src/solidlsp/language_servers/typescript_language_server.py
+++ b/src/solidlsp/language_servers/typescript_language_server.py
@@ -217,6 +217,15 @@ class TypeScriptLanguageServer(SolidLanguageServer):
         def _create_launch_command(self, core_path: str) -> list[str]:
             return [core_path, "--stdio"]
 
+    def _get_language_id_for_file(self, relative_file_path: str) -> str:
+        # JSX is parsed as TS without this, which silently truncates symbol
+        # ranges at the first multi-line JSX expression.
+        if relative_file_path.endswith(".tsx"):
+            return "typescriptreact"
+        if relative_file_path.endswith(".jsx"):
+            return "javascriptreact"
+        return self.language_id
+
     def _get_initialize_params(self, repository_absolute_path: str) -> InitializeParams:
         """
         Returns the initialize params for the TypeScript Language Server.
diff --git a/test/resources/repos/typescript/test_repo/jsx_component.tsx b/test/resources/repos/typescript/test_repo/jsx_component.tsx
new file mode 100644
index 00000000..c8dea77d
--- /dev/null
+++ b/test/resources/repos/typescript/test_repo/jsx_component.tsx
@@ -0,0 +1,44 @@
+// Regression fixture: mirrors the real-world pattern that caused
+// languageId=typescript (instead of typescriptreact) to truncate symbol
+// ranges at the first multi-line JSX expression.
+
+import * as React from "react"
+
+type SectionProps = { title: string; emphasised?: boolean }
+
+function Section({ title, emphasised }: SectionProps) {
+  return emphasised ? (
+    <h1 style={{ color: "red" }}>{title}</h1>
+  ) : (
+    <h2 style={{ color: "gray" }}>{title}</h2>
+  )
+}
+
+export function JsxComponent({ heading, items }: { heading: string; items: string[] }) {
+  const renderHeader = (title: string) =>
+    title.length > 10 ? (
+      <Section title={title} emphasised />
+    ) : (
+      <Section title={title} />
+    )
+
+  // The truncation bug used to cut JsxComponent's range right around here,
+  // hiding everything below from find_symbol. Keep this comment so the
+  // regression test can assert the function body extends past it.
+  const renderItem = (item: string, idx: number) => (
+    <li key={idx} style={{ marginBottom: 4 }}>
+      {item}
+    </li>
+  )
+
+  return (
+    <div>
+      {renderHeader(heading)}
+      <ul>{items.map(renderItem)}</ul>
+    </div>
+  )
+}
+
+export function trailingHelper(): string {
+  return "this symbol is invisible to find_symbol when JsxComponent's range is truncated"
+}
diff --git a/test/resources/repos/typescript/test_repo/tsconfig.json b/test/resources/repos/typescript/test_repo/tsconfig.json
index ba0514f5..7267a686 100644
--- a/test/resources/repos/typescript/test_repo/tsconfig.json
+++ b/test/resources/repos/typescript/test_repo/tsconfig.json
@@ -5,7 +5,8 @@
     "strict": true,
     "esModuleInterop": true,
     "forceConsistentCasingInFileNames": true,
-    "skipLibCheck": true
+    "skipLibCheck": true,
+    "jsx": "react"
   },
-  "include": ["**/*.ts"]
+  "include": ["**/*.ts", "**/*.tsx"]
 }
diff --git a/test/solidlsp/typescript/test_typescript_basic.py b/test/solidlsp/typescript/test_typescript_basic.py
index ba86ba04..2caf6b11 100644
--- a/test/solidlsp/typescript/test_typescript_basic.py
+++ b/test/solidlsp/typescript/test_typescript_basic.py
@@ -33,6 +33,37 @@ class TestTypescriptLanguageServer:
             "index.ts should reference helperFunction (tried all positions in selectionRange)"
         )
 
+    @pytest.mark.parametrize("language_server", [Language.TYPESCRIPT], indirect=True)
+    def test_tsx_symbol_range_not_truncated_by_jsx(self, language_server: SolidLanguageServer) -> None:
+        # Regression: when the language id is sent as "typescript" instead of
+        # "typescriptreact" for .tsx files, tsserver parses JSX as syntax
+        # errors and recovers by truncating the enclosing symbol's range at
+        # the first multi-line JSX expression. find_symbol then returns a
+        # body that ends mid-component and hides everything below.
+        file_path = "jsx_component.tsx"
+        roots = language_server.request_document_symbols(file_path).root_symbols
+
+        jsx_component = next((s for s in roots if s.get("name") == "JsxComponent"), None)
+        assert jsx_component is not None, "JsxComponent not found at root level of jsx_component.tsx"
+
+        end_line = jsx_component["location"]["range"]["end"]["line"]
+        # JsxComponent's body extends to line 38 (0-based 37) in the fixture;
+        # the truncation bug cut it at the first multi-line JSX (~line 21).
+        # Use a generous lower bound so the test survives small fixture edits
+        # that don't affect the regression behaviour we care about.
+        assert end_line >= 30, (
+            f"JsxComponent symbol range truncated at line {end_line + 1} (1-based); "
+            f"expected end at or past line 31 (1-based). "
+            f"This indicates the .tsx file was opened with the wrong languageId."
+        )
+
+        # The trailing helper must be visible as a top-level symbol — it lives
+        # past the truncation point and disappears entirely when the bug is
+        # active because tsserver stops emitting symbols after the parse error.
+        assert any(s.get("name") == "trailingHelper" for s in roots), (
+            "trailingHelper missing from jsx_component.tsx root symbols; tsserver likely stopped parsing at the first JSX expression."
+        )
+
     @pytest.mark.parametrize("language_server", [Language.TYPESCRIPT], indirect=True)
     def test_bare_symbol_names(self, language_server) -> None:
         all_symbols = request_all_symbols(language_server)