diff --git a/core/app/models/spree/credit_card.rb b/core/app/models/spree/credit_card.rb
index 21bc709ec10..4351b3611e4 100644
--- a/core/app/models/spree/credit_card.rb
+++ b/core/app/models/spree/credit_card.rb
@@ -17,8 +17,10 @@ class CreditCard < ActiveRecord::Base
     alias_attribute :brand, :cc_type
 
     def expiry=(expiry)
-      self[:month], self[:year] = expiry.split(" / ")
-      self[:year] = "20" + self[:year]
+      if expiry.present?
+        self[:month], self[:year] = expiry.split(" / ")
+        self[:year] = "20" + self[:year]
+      end
     end
 
     def number=(num)
diff --git a/core/spec/models/spree/credit_card_spec.rb b/core/spec/models/spree/credit_card_spec.rb
index 0142064c768..d0aa01f12db 100644
--- a/core/spec/models/spree/credit_card_spec.rb
+++ b/core/spec/models/spree/credit_card_spec.rb
@@ -150,6 +150,25 @@ def stub_rails_env(environment)
     end
   end
 
+  # Regression test for #3847 & #3896
+  context "#expiry=" do
+    it "can set with a 2-digit month and year" do
+      credit_card.expiry = '04 / 14'
+      credit_card.month = '04'
+      credit_card.year = '2014'
+    end
+
+    it "can set with a 2-digit month and 4-digit year" do
+      credit_card.expiry = '04 / 2014'
+      credit_card.month = '04'
+      credit_card.year = '2014'
+    end
+
+    it "does not blow up when passed an empty string" do
+      lambda { credit_card.expiry = '' }.should_not raise_error
+    end
+  end
+
   context "#cc_type=" do
     it "converts between the different types" do
       credit_card.cc_type = 'mastercard'