diff --git a/app/controllers/federal_subjects_controller.rb b/app/controllers/federal_subjects_controller.rb
index 53166c1..792b9ad 100644
--- a/app/controllers/federal_subjects_controller.rb
+++ b/app/controllers/federal_subjects_controller.rb
@@ -9,7 +9,7 @@ class FederalSubjectsController < ApplicationController
     @federal_subjects = policy_scope(FederalSubject).order_by_display_name
   end
 
-  # GET /federal_subjects/:id
+  # GET /federal_subjects/:number
   def show
     authorize @federal_subject
   end
@@ -17,6 +17,6 @@ class FederalSubjectsController < ApplicationController
 private
 
   def set_federal_subject
-    @federal_subject = FederalSubject.find params[:id]
+    @federal_subject = FederalSubject.find_by! number: params[:number]
   end
 end
diff --git a/app/models/federal_subject.rb b/app/models/federal_subject.rb
index be6019e..799bdd4 100644
--- a/app/models/federal_subject.rb
+++ b/app/models/federal_subject.rb
@@ -54,6 +54,10 @@ class FederalSubject < ApplicationRecord
   # Methods #
   ###########
 
+  def to_param
+    number&.to_s
+  end
+
   def display_name
     if I18n.locale == :ru
       native_name
diff --git a/app/views/federal_subjects/index.html.erb b/app/views/federal_subjects/index.html.erb
index 33b392c..ddfd970 100644
--- a/app/views/federal_subjects/index.html.erb
+++ b/app/views/federal_subjects/index.html.erb
@@ -2,9 +2,6 @@
   <table class="table">
     <thead>
       <tr>
-        <th scope="col">
-          <%= FederalSubject.human_attribute_name :id %>
-        </th>
         <th scope="col">
           <%= FederalSubject.human_attribute_name :number %>
         </th>
@@ -24,7 +21,6 @@
     <tbody>
       <% @federal_subjects.each do |federal_subject| %>
         <tr>
-          <td><%= federal_subject.id %></td>
           <td><%= federal_subject.number %></td>
           <td><%= federal_subject.display_name %></td>
           <td><%= federal_subject.centre %></td>
diff --git a/app/views/federal_subjects/show.html.erb b/app/views/federal_subjects/show.html.erb
index c1abcd6..d43e9ce 100644
--- a/app/views/federal_subjects/show.html.erb
+++ b/app/views/federal_subjects/show.html.erb
@@ -8,9 +8,6 @@
   </p>
 
   <dl class="mt-3">
-    <dt><%= FederalSubject.human_attribute_name :id %></dt>
-    <dd><%= @federal_subject.id %></dd>
-
     <dt><%= FederalSubject.human_attribute_name :number %></dt>
     <dd><%= @federal_subject.number %></dd>
 
diff --git a/config/routes.rb b/config/routes.rb
index 389aa5a..c74a8a5 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -11,7 +11,7 @@ Rails.application.routes.draw do
 
   resources :accounts, param: :nickname, only: :show
 
-  resources :federal_subjects, only: %i[index show]
+  resources :federal_subjects, param: :number, only: %i[index show]
 
   ###############
   # User routes #
diff --git a/spec/models/federal_subject_spec.rb b/spec/models/federal_subject_spec.rb
index 89a037c..f114dcc 100644
--- a/spec/models/federal_subject_spec.rb
+++ b/spec/models/federal_subject_spec.rb
@@ -15,6 +15,16 @@ RSpec.describe FederalSubject do
     it { is_expected.not_to validate_presence_of :regional_office }
   end
 
+  describe '#to_param' do
+    specify do
+      expect(subject.to_param).to be_instance_of String
+    end
+
+    specify do
+      expect(subject.to_param).to eq subject.number.to_s
+    end
+  end
+
   describe '#english_name' do
     def allow_value(*)
       super.for :english_name
diff --git a/spec/requests/federal_subjects/show_spec.rb b/spec/requests/federal_subjects/show_spec.rb
index ce73381..99087f3 100644
--- a/spec/requests/federal_subjects/show_spec.rb
+++ b/spec/requests/federal_subjects/show_spec.rb
@@ -2,13 +2,13 @@
 
 require 'rails_helper'
 
-RSpec.describe 'GET /federal_subjects/:id' do
+RSpec.describe 'GET /federal_subjects/:number' do
   let(:federal_subject) { create :federal_subject }
 
   before do
     sign_in current_account.user if current_account&.user
 
-    get "/federal_subjects/#{federal_subject.id}"
+    get "/federal_subjects/#{federal_subject.number}"
   end
 
   for_account_types nil, :guest, :usual, :superuser do