diff --git a/lib/services/address/index.js b/lib/services/address/index.js
index 4477e1ba..a557ba24 100644
--- a/lib/services/address/index.js
+++ b/lib/services/address/index.js
@@ -223,8 +223,10 @@ AddressService.prototype.transactionLeaveHandler = function(txInfo) {
  * @param {Buffer} txInfo.buffer - The transaction buffer
  * @param {Boolean} txInfo.mempool - If the transaction was accepted in the mempool
  * @param {String} txInfo.hash - The hash of the transaction
+ * @param {Function} [callback] - Optional callback
  */
-AddressService.prototype.transactionHandler = function(txInfo) {
+AddressService.prototype.transactionHandler = function(txInfo, callback) {
+  var self = this;
 
   // Basic transaction format is handled by the daemon
   // and we can safely assume the buffer is properly formatted.
@@ -237,15 +239,31 @@ AddressService.prototype.transactionHandler = function(txInfo) {
     this.transactionOutputHandler(messages, tx, i, !txInfo.mempool);
   }
 
-  // Update mempool index
-  if (txInfo.mempool) {
-    this.updateMempoolIndex(tx, true);
+  if (!callback) {
+    callback = function(err) {
+      if (err) {
+        return log.error(err);
+      }
+    };
   }
 
-  for (var key in messages) {
-    this.transactionEventHandler(messages[key]);
-    this.balanceEventHandler(null, messages[key].addressInfo);
+  function finish(err) {
+    if (err) {
+      return callback(err);
+    }
+    for (var key in messages) {
+      self.transactionEventHandler(messages[key]);
+      self.balanceEventHandler(null, messages[key].addressInfo);
+    }
+    callback();
   }
+
+  if (txInfo.mempool) {
+    self.updateMempoolIndex(tx, true, finish);
+  } else {
+    setImmediate(finish);
+  }
+
 };
 
 /**
@@ -254,7 +272,7 @@ AddressService.prototype.transactionHandler = function(txInfo) {
  * @param {Transaction} - An instance of a Bitcore Transaction
  * @param {Boolean} - Add/remove from the index
  */
-AddressService.prototype.updateMempoolIndex = function(tx, add) {
+AddressService.prototype.updateMempoolIndex = function(tx, add, callback) {
   /* jshint maxstatements: 100 */
 
   var operations = [];
@@ -362,11 +380,15 @@ AddressService.prototype.updateMempoolIndex = function(tx, add) {
 
   }
 
-  this.mempoolIndex.batch(operations, function(err) {
-    if (err) {
-      return log.error(err);
-    }
-  });
+  if (!callback) {
+    callback = function(err) {
+      if (err) {
+        return log.error(err);
+      }
+    };
+  }
+
+  this.mempoolIndex.batch(operations, callback);
 
 };
 
diff --git a/test/services/address/index.unit.js b/test/services/address/index.unit.js
index d69fa63d..e7660649 100644
--- a/test/services/address/index.unit.js
+++ b/test/services/address/index.unit.js
@@ -357,24 +357,30 @@ describe('Address Service', function() {
   });
 
   describe('#transactionHandler', function() {
-    it('will pass outputs to transactionOutputHandler and call transactionEventHandler and balanceEventHandler', function() {
+    it('will pass outputs to transactionOutputHandler and call transactionEventHandler and balanceEventHandler', function(done) {
       var txBuf = new Buffer('01000000010000000000000000000000000000000000000000000000000000000000000000ffffffff0704ffff001d0104ffffffff0100f2052a0100000043410496b538e853519c726a2c91e61ec11600ae1390813a627c66fb8be7947be63c52da7589379515d4e0a604f8141781e62294721166bf621e73a82cbf2342c858eeac00000000', 'hex');
-      var am = new AddressService({
+      var am1 = new AddressService({
         mempoolMemoryIndex: true,
         node: mocknode
       });
       var address = '12c6DSiU4Rq3P4ZxziKxzrL5LmMBrzjrJX';
       var message = {};
-      am.transactionOutputHandler = function(messages) {
+      am1.transactionOutputHandler = function(messages) {
         messages[address] = message;
       };
-      am.transactionEventHandler = sinon.spy();
-      am.balanceEventHandler = sinon.spy();
-      am.transactionHandler({
+      am1.transactionEventHandler = sinon.stub();
+      am1.balanceEventHandler = sinon.stub();
+      am1.transactionHandler({
         buffer: txBuf
+      }, function(err) {
+        if (err) {
+          throw err;
+        }
+        am1.transactionEventHandler.callCount.should.equal(1);
+        am1.balanceEventHandler.callCount.should.equal(1);
+        done();
       });
-      am.transactionEventHandler.callCount.should.equal(1);
-      am.balanceEventHandler.callCount.should.equal(1);
+
     });
   });