diff --git a/Gemfile b/Gemfile
index 85d62654c..86a57545a 100644
--- a/Gemfile
+++ b/Gemfile
@@ -20,7 +20,7 @@ gem 'paper_trail', '~> 12.0'
 gem 'pg',                        '1.2.3'
 # 1.8 is for Rails < 5.0
 gem 'ransack', '~> 2.3'
-gem 'truemail', '~> 2.3' # validates email by regexp, mail server existence and address existence
+gem 'truemail', '~> 2.4' # validates email by regexp, mail server existence and address existence
 gem 'validates_email_format_of', '1.6.3' # validates email against RFC 2822 and RFC 3696
 
 # 0.7.3 is the latest for Rails 4.2, however, it is absent on Rubygems server
diff --git a/Gemfile.lock b/Gemfile.lock
index dd41719ad..0ddf9124a 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -461,7 +461,7 @@ GEM
     thor (1.1.0)
     thread_safe (0.3.6)
     tilt (2.0.10)
-    truemail (2.3.4)
+    truemail (2.4.0)
       simpleidn (~> 0.2.1)
     tzinfo (1.2.9)
       thread_safe (~> 0.1)
@@ -568,7 +568,7 @@ DEPENDENCIES
   sidekiq
   simplecov (= 0.17.1)
   simpleidn (= 0.2.1)
-  truemail (~> 2.3)
+  truemail (~> 2.4)
   uglifier
   validates_email_format_of (= 1.6.3)
   webdrivers