diff --git a/spec/operators/throttleTime-spec.ts b/spec/operators/throttleTime-spec.ts
index fef0cd15b3..4e65054ae8 100644
--- a/spec/operators/throttleTime-spec.ts
+++ b/spec/operators/throttleTime-spec.ts
@@ -141,10 +141,10 @@ describe('throttleTime operator', () => {
   });
 
   describe('throttleTime(fn, { leading: true, trailing: true })', () => {
-    asDiagram('throttleTime(fn, { leading: true, trailing: true })')('should immediately emit the first value in each time window', () =>  {
+    asDiagram('throttleTime(fn, { leading: true, trailing: true })')('should immediately emit the first and last values in each time window', () =>  {
       const e1 =   hot('-a-xy-----b--x--cxxx--|');
       const e1subs =   '^                     !';
-      const t =  time( '----|                 ');
+      const t =  time( '----|                  ');
       const expected = '-a---y----b---x-c---x-|';
 
       const result = e1.pipe(throttleTime(t, rxTestScheduler, { leading: true, trailing: true }));
@@ -152,13 +152,23 @@ describe('throttleTime operator', () => {
       expectObservable(result).toBe(expected);
       expectSubscriptions(e1.subscriptions).toBe(e1subs);
     });
+
+    it('should emit the value if only a single one is given', () => {
+      const e1 =   hot('-a--------------------|');
+      const t =   time('----|                  ');
+      const expected = '-a--------------------|';
+
+      const result = e1.pipe(throttleTime(t, rxTestScheduler, { leading: true, trailing: true }));
+
+      expectObservable(result).toBe(expected);
+    });
   });
 
   describe('throttleTime(fn, { leading: false, trailing: true })', () => {
-    asDiagram('throttleTime(fn, { leading: false, trailing: true })')('should immediately emit the first value in each time window', () =>  {
+    asDiagram('throttleTime(fn, { leading: false, trailing: true })')('should immediately emit the last value in each time window', () =>  {
       const e1 =   hot('-a-xy-----b--x--cxxx--|');
       const e1subs =   '^                     !';
-      const t =  time( '----|                 ');
+      const t =  time( '----|                  ');
       const expected = '-----y--------x-----x-|';
 
       const result = e1.pipe(throttleTime(t, rxTestScheduler, { leading: false, trailing: true }));
@@ -167,10 +177,10 @@ describe('throttleTime operator', () => {
       expectSubscriptions(e1.subscriptions).toBe(e1subs);
     });
 
-    asDiagram('throttleTime(fn, { leading: false, trailing: true })')('should emit the last throttled value when complete', () => {
+    it('should emit the last throttled value when complete', () => {
       const e1 =   hot('-a-xy-----b--x--cxx|');
       const e1subs =   '^                  !';
-      const t =   time('----|              ');
+      const t =   time('----|               ');
       const expected = '-----y--------x----(x|)';
 
       const result = e1.pipe(throttleTime(t, rxTestScheduler, { leading: false, trailing: true }));
@@ -178,5 +188,15 @@ describe('throttleTime operator', () => {
       expectObservable(result).toBe(expected);
       expectSubscriptions(e1.subscriptions).toBe(e1subs);
     });
+
+    it('should emit the value if only a single one is given', () => {
+      const e1 =   hot('-a--------------------|');
+      const t =   time('----|                  ');
+      const expected = '-----a----------------|';
+
+      const result = e1.pipe(throttleTime(t, rxTestScheduler, { leading: false, trailing: true }));
+
+      expectObservable(result).toBe(expected);
+    });
   });
 });
diff --git a/src/internal/operators/throttleTime.ts b/src/internal/operators/throttleTime.ts
index b5da87585c..5da1540c79 100644
--- a/src/internal/operators/throttleTime.ts
+++ b/src/internal/operators/throttleTime.ts
@@ -101,6 +101,9 @@ class ThrottleTimeSubscriber<T> extends Subscriber<T> {
       this.add(this.throttled = this.scheduler.schedule<DispatchArg<T>>(dispatchNext, this.duration, { subscriber: this }));
       if (this.leading) {
         this.destination.next(value);
+      } else if (this.trailing) {
+        this._trailingValue = value;
+        this._hasTrailingValue = true;
       }
     }
   }