diff --git a/src/backupformat.js b/src/backupformat.js
index eca13d9b2..b7a163790 100644
--- a/src/backupformat.js
+++ b/src/backupformat.js
@@ -1,12 +1,15 @@
 'use strict';
 
 exports = module.exports = {
-    api
+    api,
 };
 
-const BoxError = require('./boxerror.js');
+const assert = require('assert'),
+    BoxError = require('./boxerror.js');
 
 function api(format) {
+    assert.strictEqual(typeof format, 'string');
+
     switch (format) {
     case 'tgz': return require('./backupformat/tgz.js');
     case 'rsync': return require('./backupformat/rsync.js');
diff --git a/src/backupformat/rsync.js b/src/backupformat/rsync.js
index 6c00aef11..1964e2276 100644
--- a/src/backupformat/rsync.js
+++ b/src/backupformat/rsync.js
@@ -3,6 +3,7 @@
 exports = module.exports = {
     download,
     upload,
+    getFileExtension,
 
     _saveFsMetadata: saveFsMetadata,
     _restoreFsMetadata: restoreFsMetadata
@@ -274,3 +275,9 @@ async function upload(backupTarget, remotePath, dataLayout, progressCallback) {
     await saveFsMetadata(dataLayout, `${dataLayout.localRoot()}/fsmetadata.json`);
     await sync(backupTarget, remotePath, dataLayout, progressCallback);
 }
+
+function getFileExtension(encryption) {
+    assert.strictEqual(typeof encryption, 'boolean');
+
+    return '';
+}
diff --git a/src/backupformat/tgz.js b/src/backupformat/tgz.js
index 72fa3f724..b2f37c32a 100644
--- a/src/backupformat/tgz.js
+++ b/src/backupformat/tgz.js
@@ -254,9 +254,16 @@ async function upload(backupTarget, remotePath, dataLayout, progressCallback) {
     });
 }
 
+function getFileExtension(encryption) {
+    assert.strictEqual(typeof encryption, 'boolean');
+
+    return encryption ? '.tar.gz.enc' : '.tar.gz';
+}
+
 exports = module.exports = {
     download,
     upload,
+    getFileExtension,
 
     // exported for testing
     _EnsureFileSizeStream: EnsureFileSizeStream
diff --git a/src/backuptargets.js b/src/backuptargets.js
index 125f8a3e2..db06b653d 100644
--- a/src/backuptargets.js
+++ b/src/backuptargets.js
@@ -32,7 +32,7 @@ exports = module.exports = {
 
     storageApi,
 
-    getBackupFilePath
+    getBackupFilePath,
 };
 
 const assert = require('assert'),
diff --git a/src/backuptask.js b/src/backuptask.js
index 18007abbe..779d0d95b 100644
--- a/src/backuptask.js
+++ b/src/backuptask.js
@@ -34,6 +34,14 @@ const apps = require('./apps.js'),
 
 const BACKUP_UPLOAD_CMD = path.join(__dirname, 'scripts/backupupload.js');
 
+function addFileExtension(backupTarget, remotePath) {
+    assert.strictEqual(typeof backupTarget, 'object');
+    assert.strictEqual(typeof remotePath, 'string');
+
+    const ext = backupFormat.api(backupTarget.format).getFileExtension(!!backupTarget.encyption);
+    return remotePath + ext;
+}
+
 async function checkPreconditions(backupTarget, dataLayout) {
     assert.strictEqual(typeof backupTarget, 'object');
     assert(dataLayout instanceof DataLayout, 'dataLayout must be a DataLayout');
@@ -179,11 +187,13 @@ async function uploadBoxSnapshot(backupTarget, progressCallback) {
 
     await snapshotBox(progressCallback);
 
+    const remotePath = addFileExtension(backupTarget, `snapshot/box`);
+
     const boxDataDir = safe.fs.realpathSync(paths.BOX_DATA_DIR);
     if (!boxDataDir) throw new BoxError(BoxError.FS_ERROR, `Error resolving boxdata: ${safe.error.message}`);
 
     const uploadConfig = {
-        remotePath: 'snapshot/box',
+        remotePath,
         backupTarget,
         dataLayout: new DataLayout(boxDataDir, []),
         progressTag: 'box'
@@ -225,7 +235,7 @@ async function rotateBoxBackup(backupTarget, tag, options, dependsOn, progressCa
     assert(Array.isArray(dependsOn));
     assert.strictEqual(typeof progressCallback, 'function');
 
-    const remotePath = `${tag}/box_v${constants.VERSION}`;
+    const remotePath = addFileExtension(backupTarget, `${tag}/box_v${constants.VERSION}`);
 
     debug(`rotateBoxBackup: rotating to id ${remotePath}`);
 
@@ -244,7 +254,8 @@ async function rotateBoxBackup(backupTarget, tag, options, dependsOn, progressCa
     };
 
     const id = await backups.add(data);
-    const [error] = await safe(copy(backupTarget, 'snapshot/box', remotePath, progressCallback));
+    const snapshotPath = addFileExtension(backupTarget, 'snapshot/box');
+    const [error] = await safe(copy(backupTarget, snapshotPath, remotePath, progressCallback));
     const state = error ? backups.BACKUP_STATE_ERROR : backups.BACKUP_STATE_NORMAL;
     await backups.setState(id, state);
     if (error) throw error;
@@ -271,7 +282,7 @@ async function rotateAppBackup(backupTarget, app, tag, options, progressCallback
     assert.strictEqual(typeof progressCallback, 'function');
 
     const manifest = app.manifest;
-    const remotePath = `${tag}/app_${app.fqdn}_v${manifest.version}`;
+    const remotePath = addFileExtension(backupTarget, `${tag}/app_${app.fqdn}_v${manifest.version}`);
 
     debug(`rotateAppBackup: rotating ${app.fqdn} to path ${remotePath}`);
 
@@ -290,7 +301,8 @@ async function rotateAppBackup(backupTarget, app, tag, options, progressCallback
     };
 
     const id = await backups.add(data);
-    const [error] = await safe(copy(backupTarget,  `snapshot/app_${app.id}`, remotePath, progressCallback));
+    const snapshotPath = addFileExtension(backupTarget, `snapshot/app_${app.id}`);
+    const [error] = await safe(copy(backupTarget,  snapshotPath, remotePath, progressCallback));
     const state = error ? backups.BACKUP_STATE_ERROR : backups.BACKUP_STATE_NORMAL;
     await backups.setState(id, state);
     if (error) throw error;
@@ -337,7 +349,7 @@ async function uploadAppSnapshot(backupTarget, app, progressCallback) {
 
     await snapshotApp(app, progressCallback);
 
-    const remotePath = `snapshot/app_${app.id}`;
+    const remotePath = addFileExtension(backupTarget, `snapshot/app_${app.id}`);
     const appDataDir = safe.fs.realpathSync(path.join(paths.APPS_DATA_DIR, app.id));
     if (!appDataDir) throw new BoxError(BoxError.FS_ERROR, `Error resolving appsdata: ${safe.error.message}`);
 
@@ -382,11 +394,13 @@ async function uploadMailSnapshot(backupTarget, progressCallback) {
     assert.strictEqual(typeof backupTarget, 'object');
     assert.strictEqual(typeof progressCallback, 'function');
 
+    const remotePath = addFileExtension(backupTarget, 'snapshot/mail');
+
     const mailDataDir = safe.fs.realpathSync(paths.MAIL_DATA_DIR);
     if (!mailDataDir) throw new BoxError(BoxError.FS_ERROR, `Error resolving maildata: ${safe.error.message}`);
 
     const uploadConfig = {
-        remotePath: 'snapshot/mail',
+        remotePath,
         backupTarget,
         dataLayout: new DataLayout(mailDataDir, []),
         progressTag: 'mail'
@@ -409,7 +423,7 @@ async function rotateMailBackup(backupTarget, tag, options, progressCallback) {
     assert.strictEqual(typeof options, 'object');
     assert.strictEqual(typeof progressCallback, 'function');
 
-    const remotePath = `${tag}/mail_v${constants.VERSION}`;
+    const remotePath = addFileExtension(backupTarget, `${tag}/mail_v${constants.VERSION}`);
 
     debug(`rotateMailBackup: rotating to ${remotePath}`);
 
@@ -428,7 +442,8 @@ async function rotateMailBackup(backupTarget, tag, options, progressCallback) {
     };
 
     const id = await backups.add(data);
-    const [error] = await safe(copy(backupTarget, 'snapshot/mail', remotePath, progressCallback));
+    const snapshotPath = addFileExtension(backupTarget, 'snapshot/mail');
+    const [error] = await safe(copy(backupTarget, snapshotPath, remotePath, progressCallback));
     const state = error ? backups.BACKUP_STATE_ERROR : backups.BACKUP_STATE_NORMAL;
     await backups.setState(id, state);
     if (error) throw error;
diff --git a/src/test/backuptask-test.js b/src/test/backuptask-test.js
index 220e8cbd4..408d380d8 100644
--- a/src/test/backuptask-test.js
+++ b/src/test/backuptask-test.js
@@ -70,7 +70,7 @@ describe('backuptask', function () {
 
             const result = await createBackup(defaultBackupTarget);
             expect(fs.statSync(path.join(backupConfig.backupFolder, 'snapshot/box.tar.gz')).nlink).to.be(2); // hard linked to a rotated backup
-            expect(fs.statSync(path.join(backupConfig.backupFolder, `${result.remotePath}.tar.gz`)).nlink).to.be(2);
+            expect(fs.statSync(path.join(backupConfig.backupFolder, result.remotePath)).nlink).to.be(2);
 
             backupInfo1 = result;
         });
@@ -84,8 +84,8 @@ describe('backuptask', function () {
 
             const result = await createBackup(defaultBackupTarget);
             expect(fs.statSync(path.join(backupConfig.backupFolder, 'snapshot/box.tar.gz')).nlink).to.be(2); // hard linked to a rotated backup
-            expect(fs.statSync(path.join(backupConfig.backupFolder, `${result.remotePath}.tar.gz`)).nlink).to.be(2); // hard linked to new backup
-            expect(fs.statSync(path.join(backupConfig.backupFolder, `${backupInfo1.remotePath}.tar.gz`)).nlink).to.be(1); // not hard linked anymore
+            expect(fs.statSync(path.join(backupConfig.backupFolder, result.remotePath)).nlink).to.be(2); // hard linked to new backup
+            expect(fs.statSync(path.join(backupConfig.backupFolder, backupInfo1.remotePath)).nlink).to.be(1); // not hard linked anymore
         });
 
         it('cleanup', function () {