diff --git a/types/jquery/index.d.ts b/types/jquery/index.d.ts
index 2d5543cb3a..d497b698ac 100644
--- a/types/jquery/index.d.ts
+++ b/types/jquery/index.d.ts
@@ -932,7 +932,7 @@ interface JQuery<TElement extends Node = HTMLElement> {
      * @see {@link https://api.jquery.com/height/}
      * @since 1.0
      */
-    height(): number;
+    height(): number | undefined;
     /**
      * Hide the matched elements.
      *
@@ -1024,7 +1024,7 @@ interface JQuery<TElement extends Node = HTMLElement> {
      * @see {@link https://api.jquery.com/innerHeight/}
      * @since 1.2.6
      */
-    innerHeight(): number;
+    innerHeight(): number | undefined;
     /**
      * Set the CSS inner width of each element in the set of matched elements.
      *
@@ -1044,7 +1044,7 @@ interface JQuery<TElement extends Node = HTMLElement> {
      * @see {@link https://api.jquery.com/innerWidth/}
      * @since 1.2.6
      */
-    innerWidth(): number;
+    innerWidth(): number | undefined;
     /**
      * Insert every element in the set of matched elements after the target.
      *
@@ -1534,7 +1534,7 @@ interface JQuery<TElement extends Node = HTMLElement> {
      * @see {@link https://api.jquery.com/outerHeight/}
      * @since 1.2.6
      */
-    outerHeight(includeMargin?: boolean): number;
+    outerHeight(includeMargin?: boolean): number | undefined;
     /**
      * Set the CSS outer width of each element in the set of matched elements.
      *
@@ -1554,7 +1554,7 @@ interface JQuery<TElement extends Node = HTMLElement> {
      * @see {@link https://api.jquery.com/outerWidth/}
      * @since 1.2.6
      */
-    outerWidth(includeMargin?: boolean): number;
+    outerWidth(includeMargin?: boolean): number | undefined;
     /**
      * Get the parent of each element in the current set of matched elements, optionally filtered by a selector.
      *
@@ -2177,10 +2177,11 @@ interface JQuery<TElement extends Node = HTMLElement> {
      * @since 1.3
      * @since 1.4
      */
-    toggleClass(className: string | ((this: TElement, index: number, className: string, state: boolean) => string),
-                state?: boolean): this;
+    toggleClass<TState extends boolean>(className: string | ((this: TElement, index: number, className: string, state: TState) => string),
+                                        state?: TState): this;
     /**
-     *
+     * Add or remove one or more classes from each element in the set of matched elements, depending on
+     * either the class's presence or the value of the state argument.
      *
      * @param state A boolean value to determine whether the class should be added or removed.
      * @see {@link https://api.jquery.com/toggleClass/}
@@ -2314,7 +2315,7 @@ interface JQuery<TElement extends Node = HTMLElement> {
      * @see {@link https://api.jquery.com/width/}
      * @since 1.0
      */
-    width(): number;
+    width(): number | undefined;
     /**
      * Wrap an HTML structure around each element in the set of matched elements.
      *
diff --git a/types/jquery/jquery-tests.ts b/types/jquery/jquery-tests.ts
index 02eb9f0695..03c8d18360 100644
--- a/types/jquery/jquery-tests.ts
+++ b/types/jquery/jquery-tests.ts
@@ -249,6 +249,463 @@ function JQuery() {
         }
     }
 
+    function css() {
+        // TODO: .css() getters can return 'undefined' for properties that don't exist. Consider changing the return types to reflect this after adding specialized signatures.
+        function css() {
+            // $ExpectType JQuery<HTMLElement>
+            $('p').css('cssProp', 'value');
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').css('cssProp', 20);
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').css('cssProp', function(index, value) {
+                // $ExpectType HTMLElement
+                this;
+                // $ExpectType number
+                index;
+                // $ExpectType string
+                value;
+
+                return 'value';
+            });
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').css('cssProp', function(index, value) {
+                // $ExpectType HTMLElement
+                this;
+                // $ExpectType number
+                index;
+                // $ExpectType string
+                value;
+
+                return 20;
+            });
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').css('cssProp', function(index, value) {
+                // $ExpectType HTMLElement
+                this;
+                // $ExpectType number
+                index;
+                // $ExpectType string
+                value;
+            });
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').css('cssProp', function(index, value) {
+                // $ExpectType HTMLElement
+                this;
+                // $ExpectType number
+                index;
+                // $ExpectType string
+                value;
+
+                return undefined;
+            });
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').css({
+                myProp1: 'value',
+                myProp2: 20,
+                myProp3(index, value) {
+                    // $ExpectType HTMLElement
+                    this;
+                    // $ExpectType number
+                    index;
+                    // $ExpectType string
+                    value;
+
+                    return 'value';
+                },
+                myProp4(index, value) {
+                    // $ExpectType HTMLElement
+                    this;
+                    // $ExpectType number
+                    index;
+                    // $ExpectType string
+                    value;
+
+                    return 20;
+                },
+                myProp5(index, value) {
+                    // $ExpectType HTMLElement
+                    this;
+                    // $ExpectType number
+                    index;
+                    // $ExpectType string
+                    value;
+                },
+                myProp6(index, value) {
+                    // $ExpectType HTMLElement
+                    this;
+                    // $ExpectType number
+                    index;
+                    // $ExpectType string
+                    value;
+
+                    return undefined;
+                }
+            });
+
+            // $ExpectType string
+            $('p').css('myProp');
+
+            // $ExpectType PlainObject<string>
+            $('p').css([
+                'myProp1',
+                'myProp2'
+            ]);
+        }
+
+        function height() {
+            // $ExpectType JQuery<HTMLElement>
+            $('p').height('200px');
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').height(400);
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').height(function(index, height) {
+                // $ExpectType HTMLElement
+                this;
+                // $ExpectType number
+                index;
+                // $ExpectType number
+                height;
+
+                return '200px';
+            });
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').height(function(index, height) {
+                // $ExpectType HTMLElement
+                this;
+                // $ExpectType number
+                index;
+                // $ExpectType number
+                height;
+
+                return 400;
+            });
+
+            // $ExpectType number | undefined
+            $('p').height();
+        }
+
+        function innerHeight() {
+            // $ExpectType JQuery<HTMLElement>
+            $('p').innerHeight('200px');
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').innerHeight(400);
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').innerHeight(function(index, height) {
+                // $ExpectType HTMLElement
+                this;
+                // $ExpectType number
+                index;
+                // $ExpectType number
+                height;
+
+                return '200px';
+            });
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').innerHeight(function(index, height) {
+                // $ExpectType HTMLElement
+                this;
+                // $ExpectType number
+                index;
+                // $ExpectType number
+                height;
+
+                return 400;
+            });
+
+            // $ExpectType number | undefined
+            $('p').innerHeight();
+        }
+
+        function outerHeight() {
+            // $ExpectType JQuery<HTMLElement>
+            $('p').outerHeight('200px');
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').outerHeight(400);
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').outerHeight(function(index, height) {
+                // $ExpectType HTMLElement
+                this;
+                // $ExpectType number
+                index;
+                // $ExpectType number
+                height;
+
+                return '200px';
+            });
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').outerHeight(function(index, height) {
+                // $ExpectType HTMLElement
+                this;
+                // $ExpectType number
+                index;
+                // $ExpectType number
+                height;
+
+                return 400;
+            });
+
+            // $ExpectType number | undefined
+            $('p').outerHeight();
+
+            // $ExpectType number | undefined
+            $('p').outerHeight(true);
+        }
+
+        function width() {
+            // $ExpectType JQuery<HTMLElement>
+            $('p').width('200px');
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').width(400);
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').width(function(index, width) {
+                // $ExpectType HTMLElement
+                this;
+                // $ExpectType number
+                index;
+                // $ExpectType number
+                width;
+
+                return '200px';
+            });
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').width(function(index, width) {
+                // $ExpectType HTMLElement
+                this;
+                // $ExpectType number
+                index;
+                // $ExpectType number
+                width;
+
+                return 400;
+            });
+
+            // $ExpectType number | undefined
+            $('p').width();
+        }
+
+        function innerWidth() {
+            // $ExpectType JQuery<HTMLElement>
+            $('p').innerWidth('200px');
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').innerWidth(400);
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').innerWidth(function(index, width) {
+                // $ExpectType HTMLElement
+                this;
+                // $ExpectType number
+                index;
+                // $ExpectType number
+                width;
+
+                return '200px';
+            });
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').innerWidth(function(index, width) {
+                // $ExpectType HTMLElement
+                this;
+                // $ExpectType number
+                index;
+                // $ExpectType number
+                width;
+
+                return 400;
+            });
+
+            // $ExpectType number | undefined
+            $('p').innerWidth();
+        }
+
+        function outerWidth() {
+            // $ExpectType JQuery<HTMLElement>
+            $('p').outerWidth('200px');
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').outerWidth(400);
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').outerWidth(function(index, width) {
+                // $ExpectType HTMLElement
+                this;
+                // $ExpectType number
+                index;
+                // $ExpectType number
+                width;
+
+                return '200px';
+            });
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').outerWidth(function(index, width) {
+                // $ExpectType HTMLElement
+                this;
+                // $ExpectType number
+                index;
+                // $ExpectType number
+                width;
+
+                return 400;
+            });
+
+            // $ExpectType number | undefined
+            $('p').outerWidth();
+
+            // $ExpectType number | undefined
+            $('p').outerWidth(true);
+        }
+
+        function offset() {
+            // $ExpectType JQuery<HTMLElement>
+            $('p').offset({
+                left: 20,
+                top: 50
+            });
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').offset(function(index, coords) {
+                // $ExpectType HTMLElement
+                this;
+                // $ExpectType number
+                index;
+                // $ExpectType Coordinates
+                coords;
+
+                return {
+                    left: 20,
+                    top: 50
+                };
+            });
+
+            // $ExpectType Coordinates
+            $('p').offset();
+        }
+
+        function position() {
+            // $ExpectType Coordinates
+            $('p').position();
+        }
+
+        function scrollLeft() {
+            // $ExpectType JQuery<HTMLElement>
+            $('p').scrollLeft(200);
+
+            // $ExpectType number
+            $('p').scrollLeft();
+        }
+
+        function scrollTop() {
+            // $ExpectType JQuery<HTMLElement>
+            $('p').scrollTop(200);
+
+            // $ExpectType number
+            $('p').scrollTop();
+        }
+
+        function addClass() {
+            // $ExpectType JQuery<HTMLElement>
+            $('p').addClass('className');
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').addClass(function(index, currentClassName) {
+                // $ExpectType HTMLElement
+                this;
+                // $ExpectType number
+                index;
+                // $ExpectType string
+                currentClassName;
+
+                return 'className';
+            });
+        }
+
+        function hasClass() {
+            // $ExpectType boolean
+            $('p').hasClass('className');
+        }
+
+        function removeClass() {
+            // $ExpectType JQuery<HTMLElement>
+            $('p').removeClass('className');
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').removeClass(function(index, currentClassName) {
+                // $ExpectType HTMLElement
+                this;
+                // $ExpectType number
+                index;
+                // $ExpectType string
+                currentClassName;
+
+                return 'className';
+            });
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').removeClass();
+        }
+
+        function toggleClass() {
+            // $ExpectType JQuery<HTMLElement>
+            $('p').toggleClass('className', true);
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').toggleClass(function(index, className, state) {
+                // $ExpectType HTMLElement
+                this;
+                // $ExpectType number
+                index;
+                // $ExpectType string
+                className;
+                // $ExpectType true
+                state;
+
+                return 'className';
+            }, true);
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').toggleClass('className');
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').toggleClass(function(index, className, state) {
+                // $ExpectType HTMLElement
+                this;
+                // $ExpectType number
+                index;
+                // $ExpectType string
+                className;
+                // $ExpectType boolean
+                state;
+
+                return 'className';
+            });
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').toggleClass(false);
+
+            // $ExpectType JQuery<HTMLElement>
+            $('p').toggleClass();
+        }
+    }
+
     function on() {
         function false_handler_shorthand() {
             $().on('events', false);
diff --git a/types/jquery/test/example-tests.ts b/types/jquery/test/example-tests.ts
index d2c0a8464d..961e239192 100644
--- a/types/jquery/test/example-tests.ts
+++ b/types/jquery/test/example-tests.ts
@@ -1822,8 +1822,8 @@ function examples() {
     }
 
     function finish_0() {
-        var horiz = $('#path').width() - 20,
-            vert = $('#path').height() - 20;
+        var horiz = $('#path').width()! - 20,
+            vert = $('#path').height()! - 20;
 
         var btns: { [key: string]: () => void; } = {
             bstt: function() {
@@ -1992,13 +1992,13 @@ function examples() {
         }
 
         $('#getp').click(function() {
-            showHeight('paragraph', $('p').height());
+            showHeight('paragraph', $('p').height()!);
         });
         $('#getd').click(function() {
-            showHeight('document', $(document).height());
+            showHeight('document', $(document).height()!);
         });
         $('#getw').click(function() {
-            showHeight('window', $(window).height());
+            showHeight('window', $(window).height()!);
         });
     }
 
@@ -4935,13 +4935,13 @@ function examples() {
         }
 
         $('#getp').click(function() {
-            showWidth('paragraph', $('p').width());
+            showWidth('paragraph', $('p').width()!);
         });
         $('#getd').click(function() {
-            showWidth('document', $(document).width());
+            showWidth('document', $(document).width()!);
         });
         $('#getw').click(function() {
-            showWidth('window', $(window).width());
+            showWidth('window', $(window).width()!);
         });
     }