diff --git a/lib/internal/process/promises.js b/lib/internal/process/promises.js
index f2145d425c620f..615ec7c398eff9 100644
--- a/lib/internal/process/promises.js
+++ b/lib/internal/process/promises.js
@@ -4,6 +4,7 @@ const {
   Error,
   ObjectDefineProperty,
   WeakMap,
+  Map,
 } = primordials;
 
 const {
@@ -26,7 +27,7 @@ const {
 const kHasRejectionToWarn = 1;
 
 const maybeUnhandledPromises = new WeakMap();
-const pendingUnhandledRejections = [];
+let pendingUnhandledRejections = new Map();
 const asyncHandledRejections = [];
 let lastPromiseId = 0;
 
@@ -119,32 +120,33 @@ function resolveError(type, promise, reason) {
 }
 
 function unhandledRejection(promise, reason) {
-  maybeUnhandledPromises.set(promise, {
+  const uid = ++lastPromiseId;
+  // This causes the promise to be referenced at least for one tick.
+  pendingUnhandledRejections.set(promise, {
     reason,
-    uid: ++lastPromiseId,
-    warned: false
+    uid
   });
-  // This causes the promise to be referenced at least for one tick.
-  pendingUnhandledRejections.push(promise);
   setHasRejectionToWarn(true);
 }
 
 function handledRejection(promise) {
+  if (pendingUnhandledRejections.has(promise)) {
+    pendingUnhandledRejections.delete(promise);
+    return;
+  }
   const promiseInfo = maybeUnhandledPromises.get(promise);
   if (promiseInfo !== undefined) {
     maybeUnhandledPromises.delete(promise);
-    if (promiseInfo.warned) {
-      const { uid } = promiseInfo;
-      // Generate the warning object early to get a good stack trace.
-      // eslint-disable-next-line no-restricted-syntax
-      const warning = new Error('Promise rejection was handled ' +
-                                `asynchronously (rejection id: ${uid})`);
-      warning.name = 'PromiseRejectionHandledWarning';
-      warning.id = uid;
-      asyncHandledRejections.push({ promise, warning });
-      setHasRejectionToWarn(true);
-      return;
-    }
+    const { uid } = promiseInfo;
+    // Generate the warning object early to get a good stack trace.
+    // eslint-disable-next-line no-restricted-syntax
+    const warning = new Error('Promise rejection was handled ' +
+                              `asynchronously (rejection id: ${uid})`);
+    warning.name = 'PromiseRejectionHandledWarning';
+    warning.id = uid;
+    asyncHandledRejections.push({ promise, warning });
+    setHasRejectionToWarn(true);
+    return;
   }
   if (maybeUnhandledPromises.size === 0 && asyncHandledRejections.length === 0)
     setHasRejectionToWarn(false);
@@ -197,14 +199,11 @@ function processPromiseRejections() {
     }
   }
 
-  let len = pendingUnhandledRejections.length;
-  while (len--) {
-    const promise = pendingUnhandledRejections.shift();
-    const promiseInfo = maybeUnhandledPromises.get(promise);
-    if (promiseInfo === undefined) {
-      continue;
-    }
-    promiseInfo.warned = true;
+  const pending = pendingUnhandledRejections;
+  pendingUnhandledRejections = new Map();
+  for (const [promise, promiseInfo] of pending.entries()) {
+    pending.delete(promise);
+    maybeUnhandledPromises.set(promise, promiseInfo);
     const { reason, uid } = promiseInfo;
     switch (unhandledRejectionsMode) {
       case kStrictUnhandledRejections: {
@@ -256,7 +255,7 @@ function processPromiseRejections() {
     maybeScheduledTicksOrMicrotasks = true;
   }
   return maybeScheduledTicksOrMicrotasks ||
-         pendingUnhandledRejections.length !== 0;
+         pendingUnhandledRejections.size !== 0;
 }
 
 function getErrorWithoutStack(name, message) {