diff --git a/mercurial/commands.py b/mercurial/commands.py
--- a/mercurial/commands.py
+++ b/mercurial/commands.py
@@ -247,13 +247,8 @@ def addremove(ui, repo, *pats, **opts):
     Returns 0 if all files are successfully added.
     """
     opts = pycompat.byteskwargs(opts)
-    try:
-        sim = float(opts.get('similarity') or 100)
-    except ValueError:
-        raise error.Abort(_('similarity must be a number'))
-    if sim < 0 or sim > 100:
-        raise error.Abort(_('similarity must be between 0 and 100'))
-    opts['similarity'] = sim / 100.0
+    if not opts.get('similarity'):
+        opts['similarity'] = '100'
     matcher = scmutil.match(repo[None], pats, opts)
     return scmutil.addremove(repo, matcher, "", opts)
 
diff --git a/mercurial/scmutil.py b/mercurial/scmutil.py
--- a/mercurial/scmutil.py
+++ b/mercurial/scmutil.py
@@ -754,7 +754,13 @@ def addremove(repo, matcher, prefix, opt
         opts = {}
     m = matcher
     dry_run = opts.get('dry_run')
-    similarity = float(opts.get('similarity') or 0)
+    try:
+        similarity = float(opts.get('similarity') or 0)
+    except ValueError:
+        raise error.Abort(_('similarity must be a number'))
+    if similarity < 0 or similarity > 100:
+        raise error.Abort(_('similarity must be between 0 and 100'))
+    similarity /= 100.0
 
     ret = 0
     join = lambda f: os.path.join(prefix, f)