diff --git a/tests/unit/tabs/tabs_common_deprecated.js b/tests/unit/tabs/tabs_common_deprecated.js
index 040e8cbf2..8caff1ac5 100644
--- a/tests/unit/tabs/tabs_common_deprecated.js
+++ b/tests/unit/tabs/tabs_common_deprecated.js
@@ -7,7 +7,6 @@ TestHelpers.commonWidgetTests( "tabs", {
 		event: "click",
 		heightStyle: "content",
 		hide: null,
-		fx: null,
 		idPrefix: "ui-tabs-",
 		panelTemplate: "<div></div>",
 		// show: null, // conflicts with old show callback
diff --git a/ui/jquery.ui.tabs.js b/ui/jquery.ui.tabs.js
index bc911139e..28786e5ce 100644
--- a/ui/jquery.ui.tabs.js
+++ b/ui/jquery.ui.tabs.js
@@ -1207,76 +1207,6 @@ if ( $.uiBackCompat !== false ) {
 			return this._super( type, event, _data );
 		}
 	});
-
-	// fx option
-	// The new animation options (show, hide) conflict with the old show callback.
-	// The old fx option wins over show/hide anyway (always favor back-compat).
-	// If a user wants to use the new animation API, they must give up the old API.
-	$.widget( "ui.tabs", $.ui.tabs, {
-		options: {
-			fx: null // e.g. { height: "toggle", opacity: "toggle", duration: 200 }
-		},
-
-		_getFx: function() {
-			var hide, show,
-				fx = this.options.fx;
-
-			if ( fx ) {
-				if ( $.isArray( fx ) ) {
-					hide = fx[ 0 ];
-					show = fx[ 1 ];
-				} else {
-					hide = show = fx;
-				}
-			}
-
-			return fx ? { show: show, hide: hide } : null;
-		},
-
-		_toggle: function( event, eventData ) {
-			var that = this,
-				toShow = eventData.newPanel,
-				toHide = eventData.oldPanel,
-				fx = this._getFx();
-
-			if ( !fx ) {
-				return this._super( event, eventData );
-			}
-
-			that.running = true;
-
-			function complete() {
-				that.running = false;
-				that._trigger( "activate", event, eventData );
-			}
-
-			function show() {
-				eventData.newTab.closest( "li" ).addClass( "ui-tabs-active ui-state-active" );
-
-				if ( toShow.length && fx.show ) {
-					toShow
-						.animate( fx.show, fx.show.duration, function() {
-							complete();
-						});
-				} else {
-					toShow.show();
-					complete();
-				}
-			}
-
-			// start out by hiding, then showing, then completing
-			if ( toHide.length && fx.hide ) {
-				toHide.animate( fx.hide, fx.hide.duration, function() {
-					eventData.oldTab.closest( "li" ).removeClass( "ui-tabs-active ui-state-active" );
-					show();
-				});
-			} else {
-				eventData.oldTab.closest( "li" ).removeClass( "ui-tabs-active ui-state-active" );
-				toHide.hide();
-				show();
-			}
-		}
-	});
 }
 
 })( jQuery );