3 files changed, 19 insertions, 2 deletions
diff --git a/src/cryptography/hazmat/backends/openssl/x509.py b/src/cryptography/hazmat/backends/openssl/x509.py
index 71a2fb78..94a81ce6 100644
--- a/src/cryptography/hazmat/backends/openssl/x509.py
+++ b/src/cryptography/hazmat/backends/openssl/x509.py
@@ -5,6 +5,7 @@
 from __future__ import absolute_import, division, print_function
 
 import operator
+import warnings
 
 from cryptography import utils, x509
 from cryptography.exceptions import UnsupportedAlgorithm
@@ -58,6 +59,14 @@ class _Certificate(object):
 
     @property
     def serial(self):
+        warnings.warn(
+            "Certificate serial is deprecated, use serial_number instead.",
+            utils.DeprecatedIn10
+        )
+        return self.serial_number
+
+    @property
+    def serial_number(self):
         asn1_int = self._backend._lib.X509_get_serialNumber(self._x509)
         self._backend.openssl_assert(asn1_int != self._backend._ffi.NULL)
         return _asn1_integer_to_int(self._backend, asn1_int)
diff --git a/src/cryptography/utils.py b/src/cryptography/utils.py
index 4c006278..d3e845ab 100644
--- a/src/cryptography/utils.py
+++ b/src/cryptography/utils.py
@@ -12,9 +12,11 @@ import sys
 import warnings
 
 
-# the functions deprecated in 1.0 are on an arbitrarily extended deprecation
-# cycle and should not be removed until we agree on when that cycle ends.
+# the functions deprecated in 1.0 and 1.4 are on an arbitrarily extended
+# deprecation cycle and should not be removed until we agree on when that cycle
+# ends.
 DeprecatedIn10 = DeprecationWarning
+DeprecatedIn14 = DeprecationWarning
 
 
 def read_only_property(name):
diff --git a/src/cryptography/x509/base.py b/src/cryptography/x509/base.py
index 4a22ed02..8e3f9668 100644
--- a/src/cryptography/x509/base.py
+++ b/src/cryptography/x509/base.py
@@ -69,6 +69,12 @@ class Certificate(object):
         """
 
     @abc.abstractproperty
+    def serial_number(self):
+        """
+        Returns certificate serial number
+        """
+
+    @abc.abstractproperty
     def version(self):
         """
         Returns the certificate version