diff --git a/public/language/en-GB/error.json b/public/language/en-GB/error.json
index edeb03b21d..caa23964b4 100644
--- a/public/language/en-GB/error.json
+++ b/public/language/en-GB/error.json
@@ -289,6 +289,7 @@
 	"api.503": "The route you are trying to call is not currently available due to a server configuration",
 	"api.reauth-required": "The resource you are trying to access requires (re-)authentication.",
 
+	"activitypub.not-enabled": "Federation is not enabled on this server",
 	"activitypub.invalid-id": "Unable to resolve the input id, likely as it is malformed.",
 	"activitypub.get-failed": "Unable to retrieve the specified resource.",
 	"activitypub.pubKey-not-found": "Unable to resolve public key, so payload verification cannot take place.",
diff --git a/src/activitypub/helpers.js b/src/activitypub/helpers.js
index 9a5ac54e33..dd0b0c05ff 100644
--- a/src/activitypub/helpers.js
+++ b/src/activitypub/helpers.js
@@ -28,7 +28,13 @@ const sha256 = payload => crypto.createHash('sha256').update(payload).digest('he
 
 const Helpers = module.exports;
 
+let _lastLog;
 Helpers.log = (message) => {
+	if (!message) {
+		return _lastLog;
+	}
+
+	_lastLog = message;
 	if (process.env.NODE_ENV === 'development') {
 		winston.verbose(message);
 	}
diff --git a/src/activitypub/index.js b/src/activitypub/index.js
index 2043f127a6..4a6d95b48b 100644
--- a/src/activitypub/index.js
+++ b/src/activitypub/index.js
@@ -263,6 +263,10 @@ ActivityPub.verify = async (req) => {
 };
 
 ActivityPub.get = async (type, id, uri, options) => {
+	if (!meta.config.activitypubEnabled) {
+		throw new Error('[[error:activitypub.not-enabled]]');
+	}
+
 	options = {
 		cache: true,
 		...options,
@@ -358,6 +362,10 @@ async function sendMessage(uri, id, type, payload, attempts = 1) {
 }
 
 ActivityPub.send = async (type, id, targets, payload) => {
+	if (!meta.config.activitypubEnabled) {
+		return ActivityPub.helpers.log('[activitypub/send] Federation not enabled; not sending.');
+	}
+
 	if (!Array.isArray(targets)) {
 		targets = [targets];
 	}
diff --git a/src/controllers/activitypub/index.js b/src/controllers/activitypub/index.js
index ad18451d04..ccf85b2012 100644
--- a/src/controllers/activitypub/index.js
+++ b/src/controllers/activitypub/index.js
@@ -3,6 +3,7 @@
 const nconf = require('nconf');
 const winston = require('winston');
 
+const meta = require('../../meta');
 const user = require('../../user');
 const activitypub = require('../../activitypub');
 const helpers = require('../helpers');
@@ -14,7 +15,7 @@ Controller.topics = require('./topics');
 
 Controller.fetch = async (req, res, next) => {
 	// Given a `resource` query parameter, attempts to retrieve and parse it
-	if (!req.query.resource) {
+	if (!meta.config.activitypubEnabled || !req.query.resource) {
 		return next();
 	}
 
diff --git a/src/controllers/api.js b/src/controllers/api.js
index 9b85dd2d30..3f676803cf 100644
--- a/src/controllers/api.js
+++ b/src/controllers/api.js
@@ -99,7 +99,7 @@ apiController.loadConfig = async function (req) {
 			version: fontawesome_version,
 		},
 		activitypub: {
-			probe: meta.config.activitypubProbe,
+			probe: meta.config.activitypubEnabled && meta.config.activitypubProbe,
 		},
 	};
 
diff --git a/test/activitypub.js b/test/activitypub.js
index 3465707203..be7323ad3f 100644
--- a/test/activitypub.js
+++ b/test/activitypub.js
@@ -11,7 +11,6 @@ const request = require('../src/request');
 
 const file = require('../src/file');
 const install = require('../src/install');
-const privileges = require('../src/privileges');
 const meta = require('../src/meta');
 const user = require('../src/user');
 const categories = require('../src/categories');
@@ -29,6 +28,52 @@ describe('ActivityPub integration', () => {
 		delete meta.config.activitypubEnabled;
 	});
 
+	describe.only('Master toggle', () => {
+		before(async () => {
+			delete meta.config.activitypubEnabled;
+		});
+
+		it('calls to activitypub.get should throw', async () => {
+			await assert.rejects(
+				activitypub.get('uid', 0, 'https://example.org'),
+				{ message: '[[error:activitypub.not-enabled]]' },
+			);
+		});
+
+		it('calls to activitypub.send should silently log', async () => {
+			await activitypub.send('uid', 0, ['https://example.org'], { foo: 'bar' });
+			assert.strictEqual(activitypub.helpers.log(), '[activitypub/send] Federation not enabled; not sending.')
+		});
+
+		it('request for an activitypub route should return 404 Not Found', async () => {
+			const uid = user.create({ username: utils.generateUUID() });
+			const { response } = await request.get(`${nconf.get('url')}/uid/${uid}`, {
+				headers: {
+					Accept: 'application/ld+json; profile="https://www.w3.org/ns/activitystreams"',
+				},
+			});
+
+			assert.strictEqual(response.statusCode, 404);
+		});
+
+		it('requests to the /ap endpoint should return 404 Not Found', async () => {
+			const { response } = await request.get(`${nconf.get('url')}/ap?resource=${encodeURIComponent('https://example.org')}`);
+			assert.strictEqual(response.statusCode, 404);
+		});
+
+		it('webfinger requests to a local user should not indicate an application/activity+json endpoint', async () => {
+			const username = utils.generateUUID().slice(0, 8);
+			user.create({ username });
+			const { response, body } = await request.get(`${nconf.get('url')}/.well-known/webfinger?resource=acct:${username}@${nconf.get('url_parsed').host}`);
+
+			assert.strictEqual(response.statusCode, 200);
+		});
+
+		after(() => {
+			meta.config.activitypubEnabled = 1;
+		});
+	});
+
 	describe('Helpers', () => {
 		describe('.query()', () => {