diff --git a/wpilibc/src/test/native/cpp/NotifierTest.cpp b/wpilibc/src/test/native/cpp/NotifierTest.cpp
new file mode 100644
index 0000000000..05e2e87688
--- /dev/null
+++ b/wpilibc/src/test/native/cpp/NotifierTest.cpp
@@ -0,0 +1,52 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+#include <atomic>
+
+#include "frc/Notifier.h"
+#include "frc/simulation/SimHooks.h"
+#include "gtest/gtest.h"
+
+using namespace frc;
+
+namespace {
+
+class NotifierTest : public ::testing::Test {
+ protected:
+  void SetUp() override {
+    sim::PauseTiming();
+    sim::RestartTiming();
+  }
+
+  void TearDown() override { sim::ResumeTiming(); }
+};
+
+}  // namespace
+
+TEST_F(NotifierTest, StartPeriodicAndStop) {
+  std::atomic<uint32_t> counter{0};
+
+  Notifier notifier{[&] { ++counter; }};
+  notifier.StartPeriodic(1_s);
+
+  sim::StepTiming(10.5_s);
+
+  notifier.Stop();
+  EXPECT_EQ(10u, counter);
+
+  sim::StepTiming(3_s);
+
+  EXPECT_EQ(10u, counter);
+}
+
+TEST_F(NotifierTest, StartSingle) {
+  std::atomic<uint32_t> counter{0};
+
+  Notifier notifier{[&] { ++counter; }};
+  notifier.StartSingle(1_s);
+
+  sim::StepTiming(10.5_s);
+
+  EXPECT_EQ(1u, counter);
+}
diff --git a/wpilibj/src/test/java/edu/wpi/first/wpilibj/NotifierTest.java b/wpilibj/src/test/java/edu/wpi/first/wpilibj/NotifierTest.java
new file mode 100644
index 0000000000..d6e16b634b
--- /dev/null
+++ b/wpilibj/src/test/java/edu/wpi/first/wpilibj/NotifierTest.java
@@ -0,0 +1,63 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+package edu.wpi.first.wpilibj;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import edu.wpi.first.hal.HAL;
+import edu.wpi.first.wpilibj.simulation.SimHooks;
+import java.util.concurrent.atomic.AtomicInteger;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.parallel.ResourceLock;
+
+/** Tests to see if the Notifier is working properly. */
+class NotifierTest {
+  @BeforeEach
+  void setup() {
+    HAL.initialize(500, 0);
+    SimHooks.pauseTiming();
+    SimHooks.restartTiming();
+  }
+
+  @AfterEach
+  void cleanup() {
+    SimHooks.resumeTiming();
+  }
+
+  @Test
+  @ResourceLock("timing")
+  void testStartPeriodicAndStop() {
+    AtomicInteger counter = new AtomicInteger();
+    Notifier notifier = new Notifier(counter::getAndIncrement);
+    notifier.startPeriodic(1.0);
+
+    SimHooks.stepTiming(10);
+
+    notifier.stop();
+    assertEquals(10, counter.get());
+
+    SimHooks.stepTiming(3.0);
+
+    assertEquals(10, counter.get());
+
+    notifier.close();
+  }
+
+  @Test
+  @ResourceLock("timing")
+  void testStartSingle() {
+    AtomicInteger counter = new AtomicInteger();
+    Notifier notifier = new Notifier(counter::getAndIncrement);
+    notifier.startSingle(1.0);
+
+    SimHooks.stepTiming(10.5);
+
+    assertEquals(1, counter.get());
+
+    notifier.close();
+  }
+}