diff --git a/Gemfile b/Gemfile
index 2c3378cf..1561ae4f 100644
--- a/Gemfile
+++ b/Gemfile
@@ -17,7 +17,7 @@ gem "rack-timeout"
 gem "rails", "~> 4.2.11"
 gem "recipient_interceptor"
 gem "sass-rails", "~> 5.0.1"
-gem "simple_form", "~> 3.5.0"
+gem "simple_form", "~> 4.0.0"
 gem "title"
 gem "uglifier"
 gem "unicorn"
diff --git a/Gemfile.lock b/Gemfile.lock
index e174622e..ed0dae5c 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -615,7 +615,7 @@ GEM
       sass (~> 3.0)
       slim (>= 1.3.6, < 4.0)
       terminal-table (~> 1.4)
-    builder (3.2.3)
+    builder (3.2.4)
     capybara (3.30.0)
       addressable
       mini_mime (>= 0.1.3)
@@ -636,7 +636,7 @@ GEM
     concurrent-ruby (1.1.5)
     crack (0.4.2)
       safe_yaml (~> 1.0.0)
-    crass (1.0.4)
+    crass (1.0.6)
     dalli (2.7.0)
     database_cleaner (1.3.0)
     debug_inspector (0.0.2)
@@ -717,7 +717,7 @@ GEM
       addressable (~> 2.3)
     letter_opener (1.2.0)
       launchy (~> 2.2)
-    loofah (2.2.3)
+    loofah (2.4.0)
       crass (~> 1.0.2)
       nokogiri (>= 1.5.9)
     mail (2.7.1)
@@ -730,7 +730,7 @@ GEM
     mimemagic (0.3.2)
     mini_mime (1.0.2)
     mini_portile2 (2.4.0)
-    minitest (5.11.3)
+    minitest (5.14.0)
     momentjs-rails (2.7.0)
       railties (>= 3.1)
     multi_json (1.13.1)
@@ -780,8 +780,8 @@ GEM
       activesupport (>= 4.2.0, < 5.0)
       nokogiri (~> 1.6)
       rails-deprecated_sanitizer (>= 1.0.1)
-    rails-html-sanitizer (1.0.4)
-      loofah (~> 2.2, >= 2.2.2)
+    rails-html-sanitizer (1.3.0)
+      loofah (~> 2.3)
     rails-observers (0.1.2)
       activemodel (~> 4.0)
     rails_12factor (0.0.2)
@@ -839,9 +839,9 @@ GEM
     sexp_processor (4.6.1)
     shoulda-matchers (2.7.0)
       activesupport (>= 3.0.0)
-    simple_form (3.5.0)
-      actionpack (> 4, < 5.2)
-      activemodel (> 4, < 5.2)
+    simple_form (4.0.0)
+      actionpack (> 4)
+      activemodel (> 4)
     simplecov (0.8.2)
       docile (~> 1.1.0)
       multi_json
@@ -875,7 +875,7 @@ GEM
       rails (>= 3.1)
     twitter-text (1.9.2)
       unf (~> 0.1.0)
-    tzinfo (1.2.5)
+    tzinfo (1.2.6)
       thread_safe (~> 0.1)
     uglifier (4.0.2)
       execjs (>= 0.3.0, < 3)
@@ -952,7 +952,7 @@ DEPENDENCIES
   sass-rails (~> 5.0.1)
   select2-rails
   shoulda-matchers (~> 2.7.0)
-  simple_form (~> 3.5.0)
+  simple_form (~> 4.0.0)
   simplecov
   spring
   spring-commands-rspec