diff --git a/src/feature/code_completion.cpp b/src/feature/code_completion.cpp
index 29f3ff2e..b883d5ab 100644
--- a/src/feature/code_completion.cpp
+++ b/src/feature/code_completion.cpp
@@ -296,7 +296,8 @@ class CodeCompletionCollector final : public clang::CodeCompleteConsumer {
                            llvm::StringRef overload_key,
                            llvm::StringRef signature = {},
                            llvm::StringRef return_type = {},
-                           bool is_snippet = false) {
+                           bool is_snippet = false,
+                           bool is_deprecated = false) {
             if(label.empty()) {
                 return;
             }
@@ -327,6 +328,9 @@ class CodeCompletionCollector final : public clang::CodeCompleteConsumer {
                         }
                         item.label_details = std::move(details);
                     }
+                    if(is_deprecated) {
+                        item.tags = std::vector{protocol::CompletionItemTag::Deprecated};
+                    }
                     overloads.push_back({
                         .item = std::move(item),
                         .score = *score,
@@ -355,6 +359,9 @@ class CodeCompletionCollector final : public clang::CodeCompleteConsumer {
                 }
                 item.label_details = std::move(details);
             }
+            if(is_deprecated) {
+                item.tags = std::vector{protocol::CompletionItemTag::Deprecated};
+            }
             collected.push_back(std::move(item));
         };
 
@@ -431,13 +438,15 @@ class CodeCompletionCollector final : public clang::CodeCompleteConsumer {
 
                     bool has_snippet = !snippet.empty();
                     auto insert = has_snippet ? llvm::StringRef(snippet) : llvm::StringRef(label);
+                    bool deprecated = candidate.Availability == CXAvailability_Deprecated;
                     try_add(label,
                             kind,
                             insert,
                             qualified_name.str(),
                             signature,
                             return_type,
-                            has_snippet);
+                            has_snippet,
+                            deprecated);
                     break;
                 }
             }
diff --git a/tests/unit/feature/code_completion_tests.cpp b/tests/unit/feature/code_completion_tests.cpp
index 09de96fa..8f7f7474 100644
--- a/tests/unit/feature/code_completion_tests.cpp
+++ b/tests/unit/feature/code_completion_tests.cpp
@@ -233,6 +233,33 @@ void bar() {
     }
 }
 
+TEST_CASE(DeprecatedTag) {
+    code_complete(R"cpp(
+[[deprecated]] int foooo(int x);
+int z = fo$(pos)
+)cpp");
+
+    auto it = find_item("foooo");
+    ASSERT_TRUE(it != items.end());
+    ASSERT_TRUE(it->tags.has_value());
+    auto& tags = *it->tags;
+    ASSERT_TRUE(std::ranges::find(tags, protocol::CompletionItemTag::Deprecated) != tags.end());
+}
+
+TEST_CASE(NotDeprecated) {
+    code_complete(R"cpp(
+int foooo(int x);
+int z = fo$(pos)
+)cpp");
+
+    auto it = find_item("foooo");
+    ASSERT_TRUE(it != items.end());
+    // Non-deprecated should have no Deprecated tag.
+    ASSERT_TRUE(!it->tags.has_value() ||
+                std::ranges::find(*it->tags, protocol::CompletionItemTag::Deprecated) ==
+                    it->tags->end());
+}
+
 TEST_CASE(NoBundleOverloads) {
     feature::CodeCompletionOptions opts;
     opts.bundle_overloads = false;