diff --git a/lib/secretariat/invoice.rb b/lib/secretariat/invoice.rb
index 140627b..d822867 100644
--- a/lib/secretariat/invoice.rb
+++ b/lib/secretariat/invoice.rb
@@ -238,7 +238,7 @@ def to_xml(version: 1, validate: true)
             trade_agreement = by_version(version, 'ApplicableSupplyChainTradeAgreement', 'ApplicableHeaderTradeAgreement')
 
             xml['ram'].send(trade_agreement) do
-              if buyer_reference
+              if buyer_reference.present?
                 xml['ram'].BuyerReference buyer_reference
               end
               xml['ram'].SellerTradeParty do
diff --git a/test/invoice_test.rb b/test/invoice_test.rb
index 8af2c76..106eb2b 100644
--- a/test/invoice_test.rb
+++ b/test/invoice_test.rb
@@ -884,5 +884,13 @@ def test_invoice_with_quantity_causing_sub_cent_amounts
       end
       assert_equal [], errors
     end
+
+    def test_blank_buyer_reference_is_omitted
+      invoice = make_de_invoice
+      invoice.buyer_reference = ''
+      xml = invoice.to_xml(version: 2)
+
+      refute_match(/BuyerReference/, xml)
+    end
   end
 end