diff --git a/ion/include/ion/timing.h b/ion/include/ion/timing.h
index 3a3b0c9ca..523232f8e 100644
--- a/ion/include/ion/timing.h
+++ b/ion/include/ion/timing.h
@@ -11,7 +11,7 @@ void msleep(uint32_t ms);
 
 /* millis is the number of milliseconds ellapsed since a random epoch.
  * On the device, epoch is the boot time. */
-volatile uint64_t millis();
+uint64_t millis();
 
 }
 }
diff --git a/ion/src/device/shared/drivers/timing.cpp b/ion/src/device/shared/drivers/timing.cpp
index 8ec2740ad..62306d306 100644
--- a/ion/src/device/shared/drivers/timing.cpp
+++ b/ion/src/device/shared/drivers/timing.cpp
@@ -29,7 +29,7 @@ void usleep(uint32_t us) {
   }
 }
 
-volatile uint64_t millis() {
+uint64_t millis() {
   return MillisElapsed;
 }
 
diff --git a/ion/src/shared/timing.cpp b/ion/src/shared/timing.cpp
index 7b153a136..a9bf44567 100644
--- a/ion/src/shared/timing.cpp
+++ b/ion/src/shared/timing.cpp
@@ -3,7 +3,7 @@
 
 static auto start = std::chrono::steady_clock::now();
 
-volatile uint64_t Ion::Timing::millis() {
+uint64_t Ion::Timing::millis() {
   auto elapsed = std::chrono::steady_clock::now() - start;
   return std::chrono::duration_cast<std::chrono::milliseconds>(elapsed).count();
 }