diff --git a/public/language/en-GB/error.json b/public/language/en-GB/error.json
index 353cd0fddd..e865c342bb 100644
--- a/public/language/en-GB/error.json
+++ b/public/language/en-GB/error.json
@@ -230,5 +230,16 @@
 	"topic-event-unrecognized": "Topic event '%1' unrecognized",
 
 	"cant-set-child-as-parent": "Can't set child as parent category",
-	"cant-set-self-as-parent": "Can't set self as parent category"
+	"cant-set-self-as-parent": "Can't set self as parent category",
+
+	"api.master-token-no-uid": "A master token was received without a corresponding `_uid` in the request body",
+	"api.400": "Something was wrong with the request payload you passed in.",
+	"api.401": "A valid login session was not found. Please log in and try again.",
+	"api.403": "You are not authorised to make this call",
+	"api.404": "Invalid API call",
+	"api.426": "HTTPS is required for requests to the write api, please re-send your request via HTTPS",
+	"api.429": "You have made too many requests, please try again later",
+	"api.500": "An unexpected error was encountered while attempting to service your request.",
+	"api.501": "The route you are trying to call is not implemented yet, please try again tomorrow",
+	"api.503": "The route you are trying to call is not currently available due to a server configuration"
 }
diff --git a/src/controllers/errors.js b/src/controllers/errors.js
index 1a68662d3a..eace35c6c0 100644
--- a/src/controllers/errors.js
+++ b/src/controllers/errors.js
@@ -3,6 +3,7 @@
 const nconf = require('nconf');
 const winston = require('winston');
 const validator = require('validator');
+const translator = require('../translator');
 const plugins = require('../plugins');
 const middleware = require('../middleware');
 const middlewareHelpers = require('../middleware/helpers');
@@ -57,7 +58,12 @@ exports.handleErrors = function handleErrors(err, req, res, next) { // eslint-di
 		const path = String(req.path || '');
 
 		if (path.startsWith(`${nconf.get('relative_path')}/api/v3`)) {
-			return helpers.formatApiResponse(err.message.startsWith('[[') ? 400 : 500, res, err);
+			let status = 500;
+			if (err.message.startsWith('[[')) {
+				status = 400;
+				err.message = await translator.translate(err.message);
+			}
+			return helpers.formatApiResponse(status, res, err);
 		}
 
 		winston.error(`${req.path}\n${err.stack}`);
diff --git a/src/controllers/helpers.js b/src/controllers/helpers.js
index c28cc25d57..1cedac39f1 100644
--- a/src/controllers/helpers.js
+++ b/src/controllers/helpers.js
@@ -6,6 +6,7 @@ const validator = require('validator');
 const querystring = require('querystring');
 const _ = require('lodash');
 
+const translator = require('../translator');
 const user = require('../user');
 const privileges = require('../privileges');
 const categories = require('../categories');
@@ -456,7 +457,7 @@ helpers.formatApiResponse = async (statusCode, res, payload) => {
 				break;
 		}
 
-		const returnPayload = helpers.generateError(statusCode, message);
+		const returnPayload = await helpers.generateError(statusCode, message);
 		returnPayload.response = response;
 
 		if (global.env === 'development') {
@@ -467,7 +468,8 @@ helpers.formatApiResponse = async (statusCode, res, payload) => {
 		res.status(statusCode).json(returnPayload);
 	} else if (!payload) {
 		// Non-2xx statusCode, generate predefined error
-		res.status(statusCode).json(helpers.generateError(statusCode));
+		const returnPayload = await helpers.generateError(statusCode);
+		res.status(statusCode).json(returnPayload);
 	}
 };
 
@@ -490,60 +492,50 @@ async function generateBannedResponse(res) {
 	return response;
 }
 
-helpers.generateError = (statusCode, message) => {
+helpers.generateError = async (statusCode, message) => {
 	const payload = {
 		status: {
 			code: 'internal-server-error',
-			message: 'An unexpected error was encountered while attempting to service your request.',
+			message: message || await translator.translate(`[[error:api.${statusCode}]]`),
 		},
 		response: {},
 	};
 
-	// Need to turn all these into translation strings
 	switch (statusCode) {
 		case 400:
 			payload.status.code = 'bad-request';
-			payload.status.message = message || 'Something was wrong with the request payload you passed in.';
 			break;
 
 		case 401:
 			payload.status.code = 'not-authorised';
-			payload.status.message = message || 'A valid login session was not found. Please log in and try again.';
 			break;
 
 		case 403:
 			payload.status.code = 'forbidden';
-			payload.status.message = message || 'You are not authorised to make this call';
 			break;
 
 		case 404:
 			payload.status.code = 'not-found';
-			payload.status.message = message || 'Invalid API call';
 			break;
 
 		case 426:
 			payload.status.code = 'upgrade-required';
-			payload.status.message = message || 'HTTPS is required for requests to the write api, please re-send your request via HTTPS';
 			break;
 
 		case 429:
 			payload.status.code = 'too-many-requests';
-			payload.status.message = message || 'You have made too many requests, please try again later';
 			break;
 
 		case 500:
 			payload.status.code = 'internal-server-error';
-			payload.status.message = message || payload.status.message;
 			break;
 
 		case 501:
 			payload.status.code = 'not-implemented';
-			payload.status.message = message || 'The route you are trying to call is not implemented yet, please try again tomorrow';
 			break;
 
 		case 503:
 			payload.status.code = 'service-unavailable';
-			payload.status.message = message || 'The route you are trying to call is not currently available due to a server configuration';
 			break;
 	}
 
diff --git a/src/middleware/user.js b/src/middleware/user.js
index f9addf483d..cf545ab901 100644
--- a/src/middleware/user.js
+++ b/src/middleware/user.js
@@ -65,7 +65,7 @@ module.exports = function (middleware) {
 					return true;
 				}
 
-				throw new Error('[[errors:api.master-token-no-uid]]');
+				throw new Error('[[error:api.master-token-no-uid]]');
 			} else {
 				winston.warn('[api/authenticate] Unable to find user after verifying token');
 				return true;