diff --git a/lib/modules/ens/embarkjs.js b/lib/modules/ens/embarkjs.js
index 4824c47ba..ba83ca29a 100644
--- a/lib/modules/ens/embarkjs.js
+++ b/lib/modules/ens/embarkjs.js
@@ -1,6 +1,4 @@
-/*global EmbarkJS, web3*/
-
-import namehash from 'eth-ens-namehash';
+/*global EmbarkJS, web3, registerSubDomain, namehash*/
 
 let __embarkENS = {};
 
@@ -226,50 +224,15 @@ __embarkENS.lookup = function (address, callback) {
 };
 
 __embarkENS.registerSubDomain = function (name, address, callback) {
-  const self = this;
   callback = callback || function () {};
 
-  // TODO do something when no address
-  const resolveAddr = address || '0x0000000000000000000000000000000000000000';
-  const subnode = namehash.hash(name);
-  const node = namehash.hash(`${name}.${self.registration.rootDomain}`);
-  const reverseNode = web3.utils.soliditySha3(resolveAddr.toLowerCase().substr(2) + '.addr.reverse');
-  const toSend = this.registrar.methods.register(subnode, web3.eth.defaultAccount);
-  let transaction;
+  if (!address || !web3.utils.isAddress(address)) {
+    return callback('You need to specify a valid address for the subdomain');
+  }
 
-  toSend.estimateGas()
-    // Register domain
-    .then(gasEstimated => {
-      return toSend.send({gas: gasEstimated + 1000});
-    })
-    // Set resolver for the node
-    .then(transac => {
-      if (transac.status !== "0x1" && transac.status !== "0x01") {
-        console.warn('Failed transaction', transac);
-        return callback('Failed to register. Check gas cost.');
-      }
-      transaction = transac;
-      return self.ens.methods.setResolver(node, self.resolver.options.address).send();
-    })
-    // Set address for node
-    .then(_result => {
-      return self.resolver.methods.setAddr(node, resolveAddr).send();
-    })
-    // Set resolver for the reverse node
-    .then(_result => {
-      return self.ens.methods.setResolver(reverseNode, self.resolver.options.address).send();
-    })
-    // Set name for reverse node
-    .then(_result => {
-      return self.resolver.methods.setName(reverseNode, name + '.embark.eth').send();
-    })
-    .then(_result => {
-      callback(null, transaction);
-    })
-    .catch(err => {
-      callback('Failed to register with error: ' + (err.message || err));
-      console.error(err);
-    });
+  // Register function generated by the index
+  registerSubDomain(this.ens, this.registrar, this.resolver, web3.eth.defaultAccount, name, this.registration.rootDomain,
+    web3.utils.soliditySha3(address.toLowerCase().substr(2) + '.addr.reverse'), address, callback);
 };
 
 __embarkENS.isAvailable = function () {
diff --git a/lib/modules/ens/index.js b/lib/modules/ens/index.js
index 38579f887..f0f036a25 100644
--- a/lib/modules/ens/index.js
+++ b/lib/modules/ens/index.js
@@ -104,7 +104,7 @@ class ENS {
       }
     });
 
-    let code = "";
+    let code = fs.readFileSync(utils.joinPath(__dirname, 'register.js')).toString();
     code += "\n" + fs.readFileSync(utils.joinPath(__dirname, 'embarkjs.js')).toString();
     code += "\nEmbarkJS.Names.registerProvider('ens', __embarkENS);";
 
diff --git a/lib/modules/ens/register.js b/lib/modules/ens/register.js
new file mode 100644
index 000000000..6b10d4cea
--- /dev/null
+++ b/lib/modules/ens/register.js
@@ -0,0 +1,47 @@
+const namehash = require('eth-ens-namehash');
+
+function registerSubDomain(ens, registrar, resolver, defaultAccount, subdomain, rootDomain, reverseNode, address, callback) {
+  console.log('Register', arguments);
+  const subnode = namehash.hash(subdomain);
+  const node = namehash.hash(`${subdomain}.${rootDomain}`);
+  const toSend = registrar.methods.register(subnode, defaultAccount);
+  let transaction;
+
+  toSend.estimateGas()
+  // Register domain
+    .then(gasEstimated => {
+      return toSend.send({gas: gasEstimated + 1000});
+    })
+    // Set resolver for the node
+    .then(transac => {
+      if (transac.status !== "0x1" && transac.status !== "0x01") {
+        console.warn('Failed transaction', transac);
+        return callback('Failed to register. Check gas cost.');
+      }
+      transaction = transac;
+      return ens.methods.setResolver(node, resolver.options.address).send();
+    })
+    // Set address for node
+    .then(_result => {
+      return resolver.methods.setAddr(node, address).send();
+    })
+    // Set resolver for the reverse node
+    .then(_result => {
+      return ens.methods.setResolver(reverseNode, resolver.options.address).send();
+    })
+    // Set name for reverse node
+    .then(_result => {
+      return resolver.methods.setName(reverseNode, subdomain + '.embark.eth').send();
+    })
+    .then(_result => {
+      callback(null, transaction);
+    })
+    .catch(err => {
+      callback('Failed to register with error: ' + (err.message || err));
+      console.error(err);
+    });
+}
+
+if (typeof module !== 'undefined' && module.exports) {
+  module.exports = registerSubDomain;
+}