diff --git a/toolkit/components/normandy/actions/MessagingExperimentAction.sys.mjs b/toolkit/components/normandy/actions/MessagingExperimentAction.sys.mjs
deleted file mode 100644
index 393d2cc3f28c..000000000000
--- a/toolkit/components/normandy/actions/MessagingExperimentAction.sys.mjs
+++ /dev/null
@@ -1,34 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-import { BaseStudyAction } from "resource://normandy/actions/BaseStudyAction.sys.mjs";
-
-const lazy = {};
-
-ChromeUtils.defineESModuleGetters(lazy, {
-  ActionSchemas: "resource://normandy/actions/schemas/index.sys.mjs",
-  ExperimentManager: "resource://nimbus/lib/ExperimentManager.sys.mjs",
-});
-
-const RECIPE_SOURCE = "normandy";
-
-export class MessagingExperimentAction extends BaseStudyAction {
-  constructor() {
-    super();
-    this.manager = lazy.ExperimentManager;
-  }
-  get schema() {
-    return lazy.ActionSchemas["messaging-experiment"];
-  }
-
-  async _run(recipe) {
-    if (recipe.arguments) {
-      await this.manager.onRecipe(recipe.arguments, RECIPE_SOURCE);
-    }
-  }
-
-  async _finalize() {
-    this.manager.onFinalize(RECIPE_SOURCE);
-  }
-}
diff --git a/toolkit/components/normandy/actions/schemas/index.sys.mjs b/toolkit/components/normandy/actions/schemas/index.sys.mjs
index 7ef006e90558..b21eeb092a4a 100644
--- a/toolkit/components/normandy/actions/schemas/index.sys.mjs
+++ b/toolkit/components/normandy/actions/schemas/index.sys.mjs
@@ -17,62 +17,6 @@ export const ActionSchemas = {
     },
   },
 
-  "messaging-experiment": {
-    $schema: "http://json-schema.org/draft-04/schema#",
-    title: "Messaging Experiment",
-    type: "object",
-    required: ["slug", "branches", "isEnrollmentPaused"],
-    properties: {
-      slug: {
-        description: "Unique identifier for this experiment",
-        type: "string",
-        pattern: "^[A-Za-z0-9\\-_]+$",
-      },
-      isEnrollmentPaused: {
-        description: "If true, new users will not be enrolled in the study.",
-        type: "boolean",
-        default: true,
-      },
-      branches: {
-        description: "List of experimental branches",
-        type: "array",
-        minItems: 1,
-        items: {
-          type: "object",
-          required: ["slug", "value", "ratio", "groups"],
-          properties: {
-            slug: {
-              description:
-                "Unique identifier for this branch of the experiment.",
-              type: "string",
-              pattern: "^[A-Za-z0-9\\-_]+$",
-            },
-            value: {
-              description: "Message content.",
-              type: "object",
-              properties: {},
-            },
-            ratio: {
-              description:
-                "Ratio of users who should be grouped into this branch.",
-              type: "integer",
-              minimum: 1,
-            },
-            groups: {
-              description:
-                "A list of experiment groups that can be used to exclude or select related experiments. May be empty.",
-              type: "array",
-              items: {
-                type: "string",
-                description: "Identifier of the group",
-              },
-            },
-          },
-        },
-      },
-    },
-  },
-
   "preference-rollout": {
     $schema: "http://json-schema.org/draft-04/schema#",
     title: "Change preferences permanently",
diff --git a/toolkit/components/normandy/lib/ActionsManager.sys.mjs b/toolkit/components/normandy/lib/ActionsManager.sys.mjs
index 6f811613afd7..504d1209f3a5 100644
--- a/toolkit/components/normandy/lib/ActionsManager.sys.mjs
+++ b/toolkit/components/normandy/lib/ActionsManager.sys.mjs
@@ -14,8 +14,6 @@ ChromeUtils.defineESModuleGetters(lazy, {
   BranchedAddonStudyAction:
     "resource://normandy/actions/BranchedAddonStudyAction.sys.mjs",
   ConsoleLogAction: "resource://normandy/actions/ConsoleLogAction.sys.mjs",
-  MessagingExperimentAction:
-    "resource://normandy/actions/MessagingExperimentAction.sys.mjs",
   PreferenceExperimentAction:
     "resource://normandy/actions/PreferenceExperimentAction.sys.mjs",
   PreferenceRollbackAction:
@@ -49,7 +47,6 @@ export class ActionsManager {
     "addon-rollout": lazy.AddonRolloutAction,
     "branched-addon-study": lazy.BranchedAddonStudyAction,
     "console-log": lazy.ConsoleLogAction,
-    "messaging-experiment": lazy.MessagingExperimentAction,
     "multi-preference-experiment": lazy.PreferenceExperimentAction,
     "preference-rollback": lazy.PreferenceRollbackAction,
     "preference-rollout": lazy.PreferenceRolloutAction,
diff --git a/toolkit/components/normandy/test/browser/browser.toml b/toolkit/components/normandy/test/browser/browser.toml
index 1114750fafb9..ff539a8a306e 100644
--- a/toolkit/components/normandy/test/browser/browser.toml
+++ b/toolkit/components/normandy/test/browser/browser.toml
@@ -66,8 +66,6 @@ https_first_disabled = true
 
 ["browser_actions_ConsoleLogAction.js"]
 
-["browser_actions_MessagingExperimentAction.js"]
-
 ["browser_actions_PreferenceExperimentAction.js"]
 
 ["browser_actions_PreferenceRollbackAction.js"]
diff --git a/toolkit/components/normandy/test/browser/browser_actions_MessagingExperimentAction.js b/toolkit/components/normandy/test/browser/browser_actions_MessagingExperimentAction.js
deleted file mode 100644
index 0f16ff1436fe..000000000000
--- a/toolkit/components/normandy/test/browser/browser_actions_MessagingExperimentAction.js
+++ /dev/null
@@ -1,67 +0,0 @@
-"use strict";
-
-const { BaseAction } = ChromeUtils.importESModule(
-  "resource://normandy/actions/BaseAction.sys.mjs"
-);
-const { Uptake } = ChromeUtils.importESModule(
-  "resource://normandy/lib/Uptake.sys.mjs"
-);
-const { MessagingExperimentAction } = ChromeUtils.importESModule(
-  "resource://normandy/actions/MessagingExperimentAction.sys.mjs"
-);
-
-const { _ExperimentManager, ExperimentManager } = ChromeUtils.importESModule(
-  "resource://nimbus/lib/ExperimentManager.sys.mjs"
-);
-
-decorate_task(
-  withStudiesEnabled(),
-  withStub(Uptake, "reportRecipe"),
-  async function arguments_are_validated({ reportRecipeStub }) {
-    const action = new MessagingExperimentAction();
-
-    is(
-      action.manager,
-      ExperimentManager,
-      "should set .manager to ExperimentManager singleton"
-    );
-    // Override this for the purposes of the test
-    action.manager = new _ExperimentManager();
-    await action.manager.onStartup();
-    const onRecipeStub = sinon.spy(action.manager, "onRecipe");
-
-    const recipe = {
-      id: 1,
-      arguments: {
-        slug: "foo",
-        isEnrollmentPaused: false,
-        branches: [
-          {
-            slug: "control",
-            ratio: 1,
-            groups: ["green"],
-            value: { title: "hello" },
-          },
-          {
-            slug: "variant",
-            ratio: 1,
-            groups: ["green"],
-            value: { title: "world" },
-          },
-        ],
-      },
-    };
-
-    ok(action.validateArguments(recipe.arguments), "should validate arguments");
-
-    await action.processRecipe(recipe, BaseAction.suitability.FILTER_MATCH);
-    await action.finalize();
-
-    Assert.deepEqual(reportRecipeStub.args, [[recipe, Uptake.RECIPE_SUCCESS]]);
-    Assert.deepEqual(
-      onRecipeStub.args,
-      [[recipe.arguments, "normandy"]],
-      "should call onRecipe with recipe args and 'normandy' source"
-    );
-  }
-);