diff --git a/src/netaddress.h b/src/netaddress.h
--- a/src/netaddress.h
+++ b/src/netaddress.h
@@ -193,7 +193,8 @@
     explicit CService(const struct sockaddr_in6 &addr);
 
     SERIALIZE_METHODS(CService, obj) {
-        READWRITE(obj.ip, Using<BigEndianFormatter<2>>(obj.port));
+        READWRITEAS(CNetAddr, obj);
+        READWRITE(Using<BigEndianFormatter<2>>(obj.port));
     }
 };
 
diff --git a/src/netaddress.cpp b/src/netaddress.cpp
--- a/src/netaddress.cpp
+++ b/src/netaddress.cpp
@@ -755,14 +755,12 @@
  * @returns An identifier unique to this service's address and port number.
  */
 std::vector<uint8_t> CService::GetKey() const {
-    std::vector<uint8_t> vKey;
-    vKey.resize(18);
-    memcpy(vKey.data(), ip, 16);
+    auto key = GetAddrBytes();
     // most significant byte of our port
-    vKey[16] = port / 0x100;
+    key.push_back(port / 0x100);
     // least significant byte of our port
-    vKey[17] = port & 0x0FF;
-    return vKey;
+    key.push_back(port & 0x0FF);
+    return key;
 }
 
 std::string CService::ToStringPort() const {