diff -r 2c0aa02ecd5a -r 6637b079ae45 mercurial/localrepo.py
--- a/mercurial/localrepo.py	Tue Oct 16 16:24:46 2018 +0200
+++ b/mercurial/localrepo.py	Thu Sep 20 17:27:01 2018 -0700
@@ -2895,6 +2895,9 @@
     if createopts.get('narrowfiles'):
         requirements.add(repository.NARROW_REQUIREMENT)
 
+    if createopts.get('lfs'):
+        requirements.add('lfs')
+
     return requirements
 
 def filterknowncreateopts(ui, createopts):
@@ -2913,6 +2916,7 @@
     """
     known = {
         'backend',
+        'lfs',
         'narrowfiles',
         'sharedrepo',
         'sharedrelative',
@@ -2931,6 +2935,9 @@
 
     backend
        The storage backend to use.
+    lfs
+       Repository will be created with ``lfs`` requirement. The lfs extension
+       will automatically be loaded when the repository is accessed.
     narrowfiles
        Set up repository to support narrow file storage.
     sharedrepo