diff --git a/.github/workflows/clang-tidy.yaml b/.github/workflows/clang-tidy.yaml
index 3d296602b8..c352cdecd5 100644
--- a/.github/workflows/clang-tidy.yaml
+++ b/.github/workflows/clang-tidy.yaml
@@ -17,9 +17,9 @@ jobs:
       matrix:
         include:
           - cmake_options: all-options-abiv1-preview
-            warning_limit: 142
+            warning_limit: 136
           - cmake_options: all-options-abiv2-preview
-            warning_limit: 152
+            warning_limit: 147
     env:
       CC: /usr/bin/clang-22
       CXX: /usr/bin/clang++-22
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8baba4503c..819a741b73 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -19,6 +19,9 @@ Increment the:
   namespaces
   [#4303](https://github.com/open-telemetry/opentelemetry-cpp/pull/4303)
 
+* [CODE HEALTH] Move remaining API test helpers into anonymous namespaces
+  [#4301](https://github.com/open-telemetry/opentelemetry-cpp/pull/4301)
+
 * [CODE HEALTH] Move metrics storage test fixtures into anonymous namespace
   [#4286](https://github.com/open-telemetry/opentelemetry-cpp/pull/4286)
 
diff --git a/api/test/logs/logger_test.cc b/api/test/logs/logger_test.cc
index 932a28455c..93ba579a8f 100644
--- a/api/test/logs/logger_test.cc
+++ b/api/test/logs/logger_test.cc
@@ -260,6 +260,9 @@ TEST(Logger, EventLogMethodOverloads)
 
 #endif
 
+namespace
+{
+
 // Define a basic Logger class
 class TestLogger : public Logger
 {
@@ -282,9 +285,6 @@ class TestLogger : public Logger
   }
 };
 
-namespace
-{
-
 class EnablementAwareTestLogRecord : public opentelemetry::logs::LogRecord
 {
 public:
@@ -455,8 +455,6 @@ class EnablementAwareTestLogger : public Logger
   bool enabled_impl_result_;
 };
 
-}  // namespace
-
 // Define a basic LoggerProvider class that returns an instance of the logger class defined above
 class TestProvider : public LoggerProvider
 {
@@ -678,3 +676,5 @@ TEST(Logger, EmitLogRecordWithTracePartsInArgsRoutesSpanContextVariantToEnabled)
   EXPECT_EQ(logger.last_span_context_.trace_flags(), trace_flags);
 }
 #endif  // OPENTELEMETRY_ABI_VERSION_NO >= 2
+
+}  // namespace
diff --git a/api/test/logs/provider_test.cc b/api/test/logs/provider_test.cc
index 817092b4b6..51b916e274 100644
--- a/api/test/logs/provider_test.cc
+++ b/api/test/logs/provider_test.cc
@@ -28,6 +28,9 @@ using opentelemetry::logs::Provider;
 using opentelemetry::nostd::shared_ptr;
 namespace nostd = opentelemetry::nostd;
 
+namespace
+{
+
 class TestProvider : public LoggerProvider
 {
 public:
@@ -167,3 +170,5 @@ TEST(NoopEventLoggerProvider, CreateNoopEventLogger)
 #  endif
 
 #endif
+
+}  // namespace
diff --git a/api/test/trace/propagation/detail/string_test.cc b/api/test/trace/propagation/detail/string_test.cc
index a647b9e2cf..42388f63f7 100644
--- a/api/test/trace/propagation/detail/string_test.cc
+++ b/api/test/trace/propagation/detail/string_test.cc
@@ -43,7 +43,6 @@ const SplitStringTestData split_string_test_cases[] = {
     {"foo ,bar, baz ", ',', 4, 3},
     {"00-0af7651916cd43dd8448eb211c80319c-00f067aa0ba902b7-01", '-', 4, 4},
 };
-}  // namespace
 
 // Test fixture
 class SplitStringTestFixture : public ::testing::TestWithParam<SplitStringTestData>
@@ -63,3 +62,5 @@ TEST_P(SplitStringTestFixture, SplitsAsExpected)
 INSTANTIATE_TEST_SUITE_P(SplitStringTestCases,
                          SplitStringTestFixture,
                          ::testing::ValuesIn(split_string_test_cases));
+
+}  // namespace
diff --git a/api/test/trace/provider_test.cc b/api/test/trace/provider_test.cc
index 9745c51191..7828c7d347 100644
--- a/api/test/trace/provider_test.cc
+++ b/api/test/trace/provider_test.cc
@@ -15,6 +15,9 @@ using opentelemetry::trace::TracerProvider;
 
 namespace nostd = opentelemetry::nostd;
 
+namespace
+{
+
 class TestProvider : public TracerProvider
 {
 public:
@@ -49,3 +52,5 @@ TEST(Provider, SetTracerProvider)
   Provider::SetTracerProvider(tf);
   ASSERT_EQ(tf, Provider::GetTracerProvider());
 }
+
+}  // namespace