diff --git a/MIGRATION.md b/MIGRATION.md
index 7f4ad7a0a7d6..20ff3de61010 100644
--- a/MIGRATION.md
+++ b/MIGRATION.md
@@ -6,6 +6,7 @@
     - [Imported types](#imported-types)
     - [Rolling back](#rolling-back)
   - [New addon presets](#new-addon-presets)
+  - [Removed Deprecated APIs](#removed-deprecated-apis)
   - [Client API changes](#client-api-changes)
     - [Removed Legacy Story APIs](#removed-legacy-story-apis)
     - [Can no longer add decorators/parameters after stories](#can-no-longer-add-decoratorsparameters-after-stories)
@@ -50,6 +51,7 @@
   - [Addon cssresources name attribute renamed](#addon-cssresources-name-attribute-renamed)
   - [Addon viewport uses parameters](#addon-viewport-uses-parameters)
   - [Addon a11y uses parameters, decorator renamed](#addon-a11y-uses-parameters-decorator-renamed)
+  - [Addon centered decorator deprecated](#addon-centered-decorator-deprecated)
   - [New keyboard shortcuts defaults](#new-keyboard-shortcuts-defaults)
   - [New URL structure](#new-url-structure)
   - [Rename of the `--secure` cli parameter to `--https`](#rename-of-the---secure-cli-parameter-to---https)
@@ -207,6 +209,18 @@ MyNonCheckedStory.story = {
 };
 ```
 
+### Removed Deprecated APIs
+
+In 6.0 we removed a number of APIs that were previously deprecated.
+
+See the migration guides for further details:
+
+- [Addon a11y uses parameters, decorator renamed](#addon-a11y-uses-parameters-decorator-renamed)
+- [Addon backgrounds uses parameters](#addon-backgrounds-uses-parameters)
+- [Source-loader](#source-loader)
+- [Unified docs preset](#unified-docs-preset)
+- [Addon centered decorator deprecated](#addon-centered-decorator-deprecated)
+
 ### Client API changes
 
 #### Removed Legacy Story APIs
@@ -869,6 +883,26 @@ Furthermore, the decorator `checkA11y` has been deprecated and renamed to `withA
 
 See the [a11y addon README](https://github.com/storybookjs/storybook/blob/master/addons/a11y/README.md) for more information.
 
+### Addon centered decorator deprecated
+
+If you previously had:
+
+```js
+import centered from '@storybook/addon-centered';
+```
+
+You should replace it with the React or Vue version as appropriate
+
+```js
+import centered from '@storybook/addon-centered/react';
+```
+
+or
+
+```js
+import centered from '@storybook/addon-centered/vue';
+```
+
 ### New keyboard shortcuts defaults
 
 Storybook's keyboard shortcuts are updated in 5.0, but they are configurable via the menu so if you want to set them back you can:
diff --git a/addons/a11y/package.json b/addons/a11y/package.json
index 8ba75f336139..7c53fa68d717 100644
--- a/addons/a11y/package.json
+++ b/addons/a11y/package.json
@@ -48,9 +48,7 @@
     "react-redux": "^7.0.2",
     "react-sizeme": "^2.5.2",
     "redux": "^4.0.1",
-    "regenerator-runtime": "^0.13.3",
-    "ts-dedent": "^1.1.1",
-    "util-deprecate": "^1.0.2"
+    "regenerator-runtime": "^0.13.3"
   },
   "devDependencies": {
     "@types/react-redux": "^7.0.6",
diff --git a/addons/a11y/src/index.ts b/addons/a11y/src/index.ts
index f96d86cb0d07..d3e3b5bbce65 100644
--- a/addons/a11y/src/index.ts
+++ b/addons/a11y/src/index.ts
@@ -1,7 +1,5 @@
 import { document } from 'global';
 import axe, { AxeResults, ElementContext, RunOptions, Spec } from 'axe-core';
-import deprecate from 'util-deprecate';
-import dedent from 'ts-dedent';
 
 import addons, { makeDecorator } from '@storybook/addons';
 import { EVENTS, PARAM_KEY } from './constants';
@@ -14,7 +12,7 @@ interface Setup {
   manual: boolean;
 }
 
-let setup: Setup = { element: undefined, config: {}, options: {}, manual: false };
+const setup: Setup = { element: undefined, config: {}, options: {}, manual: false };
 
 const getElement = () => {
   const storyRoot = document.getElementById('story-root');
@@ -74,34 +72,3 @@ export const withA11y = makeDecorator({
     return getStory(context);
   },
 });
-
-// TODO: REMOVE at v6.0.0
-export const withA11Y = deprecate(
-  // @ts-ignore
-  (...args: any[]) => withA11y(...args),
-  'withA11Y has been renamed withA11y'
-);
-
-// TODO: REMOVE at v6.0.0
-export const checkA11y = deprecate(
-  // @ts-ignore
-  (...args: any[]) => withA11y(...args),
-  'checkA11y has been renamed withA11y'
-);
-
-// TODO: REMOVE at v6.0.0
-export const configureA11y = deprecate(
-  (config: any) => {
-    setup = config;
-  },
-  dedent`
-    configureA11y is deprecated, please configure addon-a11y using the addParameter api:
-    
-    addParameters({
-      a11y: {
-        // ... axe options
-        element: '#root', // optional selector which element to inspect
-      },
-    });
-  `
-);
diff --git a/addons/a11y/src/preset/addDecorator.ts b/addons/a11y/src/preset/addDecorator.ts
index d4cef2e81112..be3b27b26f7a 100644
--- a/addons/a11y/src/preset/addDecorator.ts
+++ b/addons/a11y/src/preset/addDecorator.ts
@@ -1,3 +1,3 @@
-import { withA11Y } from '../index';
+import { withA11y } from '../index';
 
-export const decorators = [withA11Y];
+export const decorators = [withA11y];
diff --git a/addons/backgrounds/package.json b/addons/backgrounds/package.json
index 0a32e336c0a6..f4372022e77b 100644
--- a/addons/backgrounds/package.json
+++ b/addons/backgrounds/package.json
@@ -41,11 +41,9 @@
     "core-js": "^3.0.1",
     "memoizerific": "^1.11.3",
     "react": "^16.8.3",
-    "regenerator-runtime": "^0.13.3",
-    "util-deprecate": "^1.0.2"
+    "regenerator-runtime": "^0.13.3"
   },
   "devDependencies": {
-    "@types/util-deprecate": "^1.0.0",
     "@types/webpack-env": "^1.15.1"
   },
   "peerDependencies": {
diff --git a/addons/backgrounds/src/index.ts b/addons/backgrounds/src/index.ts
index 9352400fe35c..b9ba57b91818 100644
--- a/addons/backgrounds/src/index.ts
+++ b/addons/backgrounds/src/index.ts
@@ -1,20 +1,3 @@
-import { makeDecorator, StoryContext, StoryGetter } from '@storybook/addons';
-import deprecate from 'util-deprecate';
-
-// This decorator is kept purely so we produce a decorator that is compatible with both
-// `addDecorator(withBackgrounds(...))` and `addDecorator(withBackgrounds)`
-export const withBackgrounds = deprecate(
-  makeDecorator({
-    name: 'withBackgrounds',
-    parameterName: 'backgrounds',
-    wrapper: (getStory: StoryGetter, context: StoryContext) => {
-      return getStory(context);
-    },
-  }),
-  `Note that withBackgrounds(options) has been replaced by addParameters({ backgrounds: options})
-Read more about it in the migration guide: https://github.com/storybookjs/storybook/blob/master/MIGRATION.md`
-);
-
 if (module && module.hot && module.hot.decline) {
   module.hot.decline();
 }
diff --git a/addons/centered/package.json b/addons/centered/package.json
index 73d14a0122ed..585c7824912e 100644
--- a/addons/centered/package.json
+++ b/addons/centered/package.json
@@ -33,8 +33,7 @@
     "@storybook/addons": "6.0.0-alpha.25",
     "core-js": "^3.0.1",
     "global": "^4.3.2",
-    "regenerator-runtime": "^0.13.3",
-    "util-deprecate": "^1.0.2"
+    "regenerator-runtime": "^0.13.3"
   },
   "devDependencies": {
     "@types/mithril": "^1.1.16",
diff --git a/addons/centered/src/index.ts b/addons/centered/src/index.ts
index 1bb9f82933ae..b9ba57b91818 100644
--- a/addons/centered/src/index.ts
+++ b/addons/centered/src/index.ts
@@ -1,24 +1,3 @@
-import { window } from 'global';
-import deprecate from 'util-deprecate';
-
-import ReactCentered from './react';
-import VueCentered from './vue';
-
-// TODO: REMOVE this entire file in V6.0.0
-
-const Centered = deprecate(
-  () => (window.STORYBOOK_ENV === 'vue' ? VueCentered : ReactCentered),
-  `
-  Using "import centered from '@storybook/addon-centered'" is deprecated.
-  Please use either:
-  "import centered from '@storybook/addon-centered/react'"
-  or
-  "import centered from '@storybook/addon-centered/vue'"
-`
-)();
-
-export default Centered;
-
 if (module && module.hot && module.hot.decline) {
   module.hot.decline();
 }
diff --git a/addons/docs/angular/preset.js b/addons/docs/angular/preset.js
deleted file mode 100644
index 8d573804f8bf..000000000000
--- a/addons/docs/angular/preset.js
+++ /dev/null
@@ -1 +0,0 @@
-module.exports = require('../dist/frameworks/common/makePreset').default('angular');
diff --git a/addons/docs/html/preset.js b/addons/docs/html/preset.js
deleted file mode 100644
index c8e7b0564571..000000000000
--- a/addons/docs/html/preset.js
+++ /dev/null
@@ -1 +0,0 @@
-module.exports = require('../dist/frameworks/common/makePreset').default('html');
diff --git a/addons/docs/react/preset.js b/addons/docs/react/preset.js
deleted file mode 100644
index c92d21ffca5c..000000000000
--- a/addons/docs/react/preset.js
+++ /dev/null
@@ -1 +0,0 @@
-module.exports = require('../dist/frameworks/common/makePreset').default('react');
diff --git a/addons/docs/src/frameworks/common/makePreset.ts b/addons/docs/src/frameworks/common/makePreset.ts
deleted file mode 100644
index 08654c15063b..000000000000
--- a/addons/docs/src/frameworks/common/makePreset.ts
+++ /dev/null
@@ -1,17 +0,0 @@
-import deprecate from 'util-deprecate';
-import dedent from 'ts-dedent';
-import * as common from '../../preset';
-
-const makePreset = (framework: string) => {
-  deprecate(
-    () => {},
-    dedent`
-    Framework-specific presets are no longer-needed as of Storybook 5.3 and will be removed in 6.0.
-
-    Please use '@storybook/addon-docs/preset' instead of '@storybook/addon-docs/${framework}/preset'.
-  `
-  )();
-  return common;
-};
-
-export default makePreset;
diff --git a/addons/docs/vue/preset.js b/addons/docs/vue/preset.js
deleted file mode 100644
index 09cb6c49e5e5..000000000000
--- a/addons/docs/vue/preset.js
+++ /dev/null
@@ -1 +0,0 @@
-module.exports = require('../dist/frameworks/common/makePreset').default('vue');
diff --git a/addons/docs/web-components/preset.js b/addons/docs/web-components/preset.js
deleted file mode 100644
index bb92eefa1c08..000000000000
--- a/addons/docs/web-components/preset.js
+++ /dev/null
@@ -1 +0,0 @@
-module.exports = require('../dist/frameworks/common/makePreset').default('web-components');
diff --git a/addons/storysource/loader.js b/addons/storysource/loader.js
deleted file mode 100644
index cde76952e169..000000000000
--- a/addons/storysource/loader.js
+++ /dev/null
@@ -1,6 +0,0 @@
-const deprecate = require('util-deprecate');
-
-deprecate(() => {},
-'@storybook/addon-storysource/loader is deprecated, please use @storybook/source-loader instead.')();
-
-module.exports = require('@storybook/source-loader');
diff --git a/addons/storysource/package.json b/addons/storysource/package.json
index 4e1176b48378..1557223153cd 100644
--- a/addons/storysource/package.json
+++ b/addons/storysource/package.json
@@ -43,8 +43,7 @@
     "prop-types": "^15.7.2",
     "react": "^16.9.17",
     "react-syntax-highlighter": "^11.0.2",
-    "regenerator-runtime": "^0.13.3",
-    "util-deprecate": "^1.0.2"
+    "regenerator-runtime": "^0.13.3"
   },
   "devDependencies": {
     "@types/react": "^16.9.19",
diff --git a/addons/storysource/src/index.ts b/addons/storysource/src/index.ts
index 6f62c1dcf725..a5cd9202f547 100644
--- a/addons/storysource/src/index.ts
+++ b/addons/storysource/src/index.ts
@@ -1,7 +1,6 @@
 import { ADDON_ID, PANEL_ID } from './events';
-import { withStorySource } from './preview';
 
-export { ADDON_ID, PANEL_ID, withStorySource };
+export { ADDON_ID, PANEL_ID };
 
 if (module && module.hot && module.hot.decline) {
   module.hot.decline();
diff --git a/addons/storysource/src/preview.ts b/addons/storysource/src/preview.ts
deleted file mode 100644
index e36004385aec..000000000000
--- a/addons/storysource/src/preview.ts
+++ /dev/null
@@ -1,11 +0,0 @@
-import { logger } from '@storybook/client-logger';
-
-export function withStorySource(source: string, locationsMap = {}) {
-  logger.error(
-    '@storybook/addon-storysource/withStorySource is deprecated, please use paramaters instead.'
-  );
-
-  return (storyFn: (context: any) => React.ReactNode, context: any) => {
-    return storyFn(context);
-  };
-}