diff --git a/types/ember/index.d.ts b/types/ember/index.d.ts
index 5a2a654cbc..3c0d3c15cf 100755
--- a/types/ember/index.d.ts
+++ b/types/ember/index.d.ts
@@ -1734,11 +1734,11 @@ declare module 'ember' {
                 key: keyof this,
                 target: Target,
                 method: ObserverMethod<Target, this>
-            ): void;
+            ): this;
             addObserver(
                 key: keyof this,
                 method: ObserverMethod<this, this>
-            ): void;
+            ): this;
             /**
              * Remove an observer you have previously registered on this object. Pass
              * the same key, target, and method you passed to `addObserver()` and your
@@ -1748,11 +1748,11 @@ declare module 'ember' {
                 key: keyof this,
                 target: Target,
                 method: ObserverMethod<Target, this>
-            ): any;
+            ): this;
             removeObserver(
                 key: keyof this,
                 method: ObserverMethod<this, this>
-            ): any;
+            ): this;
             /**
              * Retrieves the value of a property, or a default value in the case that the
              * property returns `undefined`.
@@ -3147,33 +3147,33 @@ declare module 'ember' {
         /**
          * Specify a method that observes property changes.
          */
-        function observer(key1: string, func: (target: any, key: string) => void): void;
-        function observer(
+        function observer<Fn extends (target: any, key: string) => void>(key1: string, func: Fn): Fn;
+        function observer<Fn extends (target: any, key: string) => void>(
             key1: string,
             key2: string,
-            func: (target: any, key: string) => void
-        ): void;
-        function observer(
+            func: Fn
+        ): Fn;
+        function observer<Fn extends (target: any, key: string) => void>(
             key1: string,
             key2: string,
             key3: string,
-            func: (target: any, key: string) => void
-        ): void;
-        function observer(
+            func: Fn
+        ): Fn;
+        function observer<Fn extends (target: any, key: string) => void>(
             key1: string,
             key2: string,
             key3: string,
             key4: string,
-            func: (target: any, key: string) => void
-        ): void;
-        function observer(
+            func: Fn
+        ): Fn;
+        function observer<Fn extends (target: any, key: string) => void>(
             key1: string,
             key2: string,
             key3: string,
             key4: string,
             key5: string,
-            func: (target: any, key: string) => void
-        ): void;
+            func: Fn
+        ): Fn;
         /**
          * Adds an observer on a property.
          */
diff --git a/types/ember/test/private/observable-tests.ts b/types/ember/test/private/observable-tests.ts
index be3d4bd69f..1a789cc114 100644
--- a/types/ember/test/private/observable-tests.ts
+++ b/types/ember/test/private/observable-tests.ts
@@ -69,13 +69,13 @@ class DemoObservable implements Observable {
     notifyPropertyChange(keyName: string): this {
         throw new Error("Method not implemented.");
     }
-    addObserver<Target>(key: keyof this, target: Target, method: keyof Target | ((this: Target, sender: this, key: string, value: any, rev: number) => void)): void;
-    addObserver<K extends keyof this>(key: K, method: keyof this | ((this: this, sender: this, key: K, value: this[K], rev: number) => void)): void;
+    addObserver<Target>(key: keyof this, target: Target, method: keyof Target | ((this: Target, sender: this, key: string, value: any, rev: number) => void)): any;
+    addObserver<K extends keyof this>(key: K, method: keyof this | ((this: this, sender: this, key: K, value: this[K], rev: number) => void)): any;
     addObserver(key: any, target: any, method?: any) {
         throw new Error("Method not implemented.");
     }
-    removeObserver<Target>(key: keyof this, target: Target, method: keyof Target | ((this: Target, sender: this, key: string, value: any, rev: number) => void)): void;
-    removeObserver(key: keyof this, method: keyof this | ((this: this, sender: this, key: string, value: any, rev: number) => void)): void;
+    removeObserver<Target>(key: keyof this, target: Target, method: keyof Target | ((this: Target, sender: this, key: string, value: any, rev: number) => void)): any;
+    removeObserver(key: keyof this, method: keyof this | ((this: this, sender: this, key: string, value: any, rev: number) => void)): any;
     removeObserver(key: any, target: any, method?: any): void {
         throw new Error("Method not implemented.");
     }