diff --git a/qutebrowser/utils/urlmatch.py b/qutebrowser/utils/urlmatch.py
index 76a72c32e..5efa5cfb8 100644
--- a/qutebrowser/utils/urlmatch.py
+++ b/qutebrowser/utils/urlmatch.py
@@ -25,6 +25,7 @@ https://cs.chromium.org/chromium/src/extensions/common/url_pattern.cc
 https://cs.chromium.org/chromium/src/extensions/common/url_pattern.h
 """
 
+import ipaddress
 import fnmatch
 import contextlib
 import urllib.parse
@@ -205,11 +206,10 @@ class UrlPattern:
         if not self._match_subdomains:
             return False
 
-        # FIXME
         # We don't do subdomain matching against IP addresses, so we can give up now
         # if the test host is an IP address.
-        # if (test.HostIsIPAddress())
-        #   return false;
+        if not utils.raises(ValueError, ipaddress.ip_address, host):
+            return False
 
         # Check if the test host is a subdomain of our host.
         if len(host) <= (len(self._host) + 1):
diff --git a/tests/unit/utils/test_urlmatch.py b/tests/unit/utils/test_urlmatch.py
index cc5f4006a..624736a22 100644
--- a/tests/unit/utils/test_urlmatch.py
+++ b/tests/unit/utils/test_urlmatch.py
@@ -187,3 +187,27 @@ class TestMatchGlobEscaping:
     ])
     def test_urls(self, up, url, expected):
         assert up.matches(QUrl(url)) == expected
+
+
+class TestMatchIpAddresses:
+
+    @pytest.mark.parametrize('pattern, host, match_subdomains', [
+        ("http://127.0.0.1/*", "127.0.0.1", False),
+        ("http://*.0.0.1/*", "0.0.1", True),
+    ])
+    def test_attrs(self, pattern, host, match_subdomains):
+        up = urlmatch.UrlPattern(pattern)
+        assert up._scheme == 'http'
+        assert up._host == host
+        assert up._match_subdomains == match_subdomains
+        assert not up._match_all
+        assert up._path == '/*'
+
+    @pytest.mark.parametrize('pattern, expected', [
+        ("http://127.0.0.1/*", True),
+        # No subdomain matching is done with IPs
+        ("http://*.0.0.1/*", False),
+    ])
+    def test_urls(self, pattern, expected):
+        up = urlmatch.UrlPattern(pattern)
+        assert up.matches(QUrl("http://127.0.0.1")) == expected