diff --git a/app/models/verification/sms.rb b/app/models/verification/sms.rb
index 19e0bf041..1a013f1d8 100644
--- a/app/models/verification/sms.rb
+++ b/app/models/verification/sms.rb
@@ -4,7 +4,7 @@ class Verification::Sms
   attr_accessor :user, :phone, :confirmation_code
 
   validates_presence_of :phone
-  validates :phone, length: { is: 9 }
+  validates :phone, format: { with: /\A[\d \+]+\z/ }
   validate :uniqness_phone
 
   def uniqness_phone
diff --git a/spec/models/sms_spec.rb b/spec/models/sms_spec.rb
index f52ff3c6e..83723cb3c 100644
--- a/spec/models/sms_spec.rb
+++ b/spec/models/sms_spec.rb
@@ -7,9 +7,16 @@ describe Verification::Sms do
   end
 
   it "should validate uniqness of phone" do
-    user = create(:user, confirmed_phone: "699999999")
+    create(:user, confirmed_phone: "699999999")
     sms = Verification::Sms.new(phone: "699999999")
     expect(sms).to_not be_valid
   end
 
-end
\ No newline at end of file
+  it "only allows spaces, numbers and the + sign" do
+    expect(build(:verification_sms, phone: "0034 666666666")).to be_valid
+    expect(build(:verification_sms, phone: "+34 666666666")).to be_valid
+    expect(build(:verification_sms, phone: "hello there")).to_not be_valid
+    expect(build(:verification_sms, phone: "555; DROP TABLE USERS")).to_not be_valid
+  end
+
+end