diff --git a/app/controllers/accept_account_invitations_controller.rb b/app/controllers/accept_account_invitations_controller.rb
index 5c5a717b..6ba0d020 100644
--- a/app/controllers/accept_account_invitations_controller.rb
+++ b/app/controllers/accept_account_invitations_controller.rb
@@ -5,7 +5,12 @@ def show
     return if user_signed_in?
 
     session[:after_sign_in_url] = request.fullpath
-    redirect_to new_user_session_url(email: AccountInvitation.find_by!(token: ps.fetch(:token)).email)
+
+    invitee_email = AccountInvitation.find_by!(token: ps.fetch(:token)).email
+    user = User.find_by(email: invitee_email)
+    redirect_url = user ? new_user_session_url(email: invitee_email) : new_user_registration_url(email: invitee_email)
+
+    redirect_to redirect_url
   end
 
   def update
diff --git a/app/controllers/users/registrations_controller.rb b/app/controllers/users/registrations_controller.rb
index 43ad96a7..78f3e84d 100644
--- a/app/controllers/users/registrations_controller.rb
+++ b/app/controllers/users/registrations_controller.rb
@@ -1,4 +1,12 @@
 class Users::RegistrationsController < Devise::RegistrationsController
+  def new
+    if params.key?(:email)
+      self.resource = User.new(email: params[:email])
+    else
+      super
+    end
+  end
+
   def create
     super do |user|
       user.create_account(name: user.email, email: user.email) if user.persisted?
@@ -10,4 +18,13 @@ def create
   def devise_mapping
     @devise_mapping ||= Devise.mappings[:user]
   end
+
+  private
+
+  def after_sign_up_path_for(resource)
+    after_sign_in_url = session.delete(:after_sign_in_url)
+    return after_sign_in_url if after_sign_in_url.present?
+
+    super
+  end
 end
\ No newline at end of file
diff --git a/spec/controllers/accept_account_invitations_spec.rb b/spec/controllers/accept_account_invitations_spec.rb
index f1777968..5201dbcb 100644
--- a/spec/controllers/accept_account_invitations_spec.rb
+++ b/spec/controllers/accept_account_invitations_spec.rb
@@ -6,7 +6,7 @@
   describe '#show' do
     let(:account) { create(:account, :parent) }
     let(:user) { create(:user, account: account) }
-    let(:second_user) { create(:user, account: account) }
+    let(:second_user) { create(:user) }
 
     let!(:account_invitation) { create(:account_invitation, user: user, account: account, email: second_user.email) }
 
@@ -21,6 +21,15 @@
       end
     end
 
+    context 'when the user not signed up' do
+      let(:account_invitation) { create(:account_invitation, user: user, account: account) }
+
+      it 'redirects to registration url with email' do
+        subject
+        expect(response).to redirect_to(new_user_registration_url(email: account_invitation.email))
+      end
+    end
+
     context 'when the user signed in' do
       before { sign_in second_user }