diff --git a/include/uv-win.h b/include/uv-win.h
index 4abb294c05..70a5c8ff8a 100644
--- a/include/uv-win.h
+++ b/include/uv-win.h
@@ -315,7 +315,9 @@ RB_HEAD(uv_timer_tree_s, uv_timer_s);
     /* The loop's I/O completion port */                                      \
   HANDLE iocp;                                                                \
   /* The current time according to the event loop. in msecs. */               \
-  uint64_t time;                                                              \
+  /* Don't access these fields directly. Use uv__loop_time() instead. */      \
+  uint64_t cached_time;                                                       \
+  int cached_time_is_valid;                                                   \
   /* Tail of a single-linked circular queue of pending reqs. If the queue */  \
   /* is empty, tail_ is NULL. If there is only one item, */                   \
   /* tail_->next_req == tail_ */                                              \
diff --git a/src/unix/timer.c b/src/unix/timer.c
index ca3ec3db95..c77b065ae6 100644
--- a/src/unix/timer.c
+++ b/src/unix/timer.c
@@ -26,6 +26,11 @@
 #include <limits.h>
 
 
+uint64_t uv_now(const uv_loop_t* loop) {
+  return loop->time;
+}
+
+
 static int timer_less_than(const struct heap_node* ha,
                            const struct heap_node* hb) {
   const uv_timer_t* a;
diff --git a/src/uv-common.c b/src/uv-common.c
index 97727baa54..733c8f0f1e 100644
--- a/src/uv-common.c
+++ b/src/uv-common.c
@@ -391,12 +391,6 @@ void uv_stop(uv_loop_t* loop) {
 }
 
 
-uint64_t uv_now(const uv_loop_t* loop) {
-  return loop->time;
-}
-
-
-
 size_t uv__count_bufs(const uv_buf_t bufs[], unsigned int nbufs) {
   unsigned int i;
   size_t bytes;
diff --git a/src/win/core.c b/src/win/core.c
index c9e4c88fa7..a3c84ade0f 100644
--- a/src/win/core.c
+++ b/src/win/core.c
@@ -133,11 +133,8 @@ int uv_loop_init(uv_loop_t* loop) {
   if (loop->iocp == NULL)
     return uv_translate_sys_error(GetLastError());
 
-  /* To prevent uninitialized memory access, loop->time must be intialized
-   * to zero before calling uv_update_time for the first time.
-   */
-  loop->time = 0;
-  uv_update_time(loop);
+  loop->cached_time = 0;
+  loop->cached_time_is_valid = 0;
 
   QUEUE_INIT(&loop->wq);
   QUEUE_INIT(&loop->handle_queue);
diff --git a/src/win/internal.h b/src/win/internal.h
index d87402b73a..36c2293a5d 100644
--- a/src/win/internal.h
+++ b/src/win/internal.h
@@ -245,6 +245,7 @@ void uv_timer_endgame(uv_loop_t* loop, uv_timer_t* handle);
 DWORD uv__next_timeout(const uv_loop_t* loop);
 void uv__time_forward(uv_loop_t* loop, uint64_t msecs);
 void uv_process_timers(uv_loop_t* loop);
+uint64_t uv__loop_time(const uv_loop_t* loop);
 
 
 /*
diff --git a/src/win/timer.c b/src/win/timer.c
index 0da541a2c8..8e93f02f5c 100644
--- a/src/win/timer.c
+++ b/src/win/timer.c
@@ -33,14 +33,34 @@
 
 
 void uv_update_time(uv_loop_t* loop) {
-  uint64_t new_time = uv__hrtime(UV__MILLISEC);
-  if (new_time > loop->time) {
-    loop->time = new_time;
-  }
+  /* Invalidate the loop time, so that the next invocation of uv__loop_time()
+   * will actually update it.
+   */
+  loop->cached_time_is_valid = 0;
 }
 
 void uv__time_forward(uv_loop_t* loop, uint64_t msecs) {
-  loop->time += msecs;
+  loop->cached_time += msecs;
+  loop->cached_time_is_valid = 0;
+}
+
+uint64_t uv__loop_time(const uv_loop_t* loop) {
+  uv_loop_t* mutable_loop;
+  uint64_t new_time;
+  if (!loop->cached_time_is_valid) {
+    new_time = uv__hrtime(UV__MILLISEC);
+    mutable_loop = (uv_loop_t*) loop;
+    if (new_time > mutable_loop->cached_time) {
+      mutable_loop->cached_time = new_time;
+    }
+    mutable_loop->cached_time_is_valid = 1;
+  }
+
+  return loop->cached_time;
+}
+
+uint64_t uv_now(const uv_loop_t* loop) {
+  return uv__loop_time(loop);
 }
 
 
@@ -104,7 +124,7 @@ int uv_timer_start(uv_timer_t* handle, uv_timer_cb timer_cb, uint64_t timeout,
     uv_timer_stop(handle);
 
   handle->timer_cb = timer_cb;
-  handle->due = get_clamped_due_time(loop->time, timeout);
+  handle->due = get_clamped_due_time(uv__loop_time(loop), timeout);
   handle->repeat = repeat;
   uv__handle_start(handle);
 
@@ -168,7 +188,7 @@ DWORD uv__next_timeout(const uv_loop_t* loop) {
    */
   timer = RB_MIN(uv_timer_tree_s, &((uv_loop_t*)loop)->timers);
   if (timer) {
-    delta = timer->due - loop->time;
+    delta = timer->due - uv__loop_time(loop);
     if (delta >= UINT_MAX - 1) {
       /* A timeout value of UINT_MAX means infinite, so that's no good. */
       return UINT_MAX - 1;
@@ -190,7 +210,7 @@ void uv_process_timers(uv_loop_t* loop) {
 
   /* Call timer callbacks */
   for (timer = RB_MIN(uv_timer_tree_s, &loop->timers);
-       timer != NULL && timer->due <= loop->time;
+       timer != NULL && timer->due <= uv__loop_time(loop);
        timer = RB_MIN(uv_timer_tree_s, &loop->timers)) {
 
     uv_timer_stop(timer);