diff --git a/CHANGELOG.md b/CHANGELOG.md
index 22a8d88541..9cfa5408d4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -18,6 +18,7 @@
 * [#988](https://github.com/intridea/grape/pull/988): Fixed duplicate identical endpoints - [@u2](https://github.com/u2).
 * [#936](https://github.com/intridea/grape/pull/936): Fixed default params processing for optional groups - [@dm1try](https://github.com/dm1try).
 * [#942](https://github.com/intridea/grape/pull/942): Fixed forced presence for optional params when based on a reused entity that was also required in another context - [@croeck](https://github.com/croeck).
+* [#1001](https://github.com/intridea/grape/pull/1001): Fixed calling endpoint with specified format with format in its path - [@hodak](https://github.com/hodak).
 
 * Your contribution here.
 
diff --git a/README.md b/README.md
index cd6b4a1400..375ed63abc 100644
--- a/README.md
+++ b/README.md
@@ -1680,7 +1680,7 @@ end
 ```
 
 You can have your API only respond to a single format with `format`. If you use this, the API will **not** respond to file
-extensions. For example, consider the following API.
+extensions other than specified in `format`. For example, consider the following API.
 
 ```ruby
 class SingleFormatAPI < Grape::API
@@ -1693,7 +1693,8 @@ end
 ```
 
 * `GET /hello` will respond with JSON.
-* `GET /hello.xml`, `GET /hello.json`, `GET /hello.foobar`, or *any* other extension will respond with an HTTP 404 error code.
+* `GET /hello.json` will respond with JSON.
+* `GET /hello.xml`, `GET /hello.foobar`, or *any* other extension will respond with an HTTP 404 error code.
 * `GET /hello?format=xml` will respond with an HTTP 406 error code, because the XML format specified by the request parameter
   is not supported.
 * `GET /hello` with an `Accept: application/xml` header will still respond with JSON, since it could not negotiate a
diff --git a/UPGRADING.md b/UPGRADING.md
index 734aa950dc..18dc895940 100644
--- a/UPGRADING.md
+++ b/UPGRADING.md
@@ -56,6 +56,26 @@ error!(e)
 
 See [#889](https://github.com/intridea/grape/issues/889) for more information.
 
+#### Changes to routes when using `format`
+
+Now it's possible to call API with proper suffix when single `format` is defined. I. e.
+
+```ruby
+class API < Grape::API
+  format :json
+
+  get :hello do
+    { hello: 'world' }
+  end
+end
+```
+
+Will respond with JSON to `/hello` **and** `/hello.json`.
+
+Will respond with 404 to `/hello.xml`, `/hello.txt` etc.
+
+See the [#1001](https://github.com/intridea/grape/pull/1001) for more info.
+
 ### Upgrading to >= 0.11.0
 
 #### Added Rack 1.6.0 support
diff --git a/lib/grape/path.rb b/lib/grape/path.rb
index 15542def7c..ef5ff69b99 100644
--- a/lib/grape/path.rb
+++ b/lib/grape/path.rb
@@ -38,7 +38,7 @@ def has_path?
 
     def suffix
       if uses_specific_format?
-        ''
+        "(.#{settings[:format]})"
       elsif !uses_path_versioning? || (has_namespace? || has_path?)
         '(.:format)'
       else
diff --git a/spec/grape/api/deeply_included_options_spec.rb b/spec/grape/api/deeply_included_options_spec.rb
new file mode 100644
index 0000000000..4ab111c864
--- /dev/null
+++ b/spec/grape/api/deeply_included_options_spec.rb
@@ -0,0 +1,56 @@
+require 'spec_helper'
+
+module API
+  module Defaults
+    extend ActiveSupport::Concern
+    included do
+      format :json
+    end
+  end
+
+  module Admin
+    module Defaults
+      extend ActiveSupport::Concern
+      include API::Defaults
+    end
+
+    class Users < Grape::API
+      include API::Admin::Defaults
+
+      resource :users do
+        get do
+          status 200
+        end
+      end
+    end
+  end
+end
+
+class Main < Grape::API
+  mount API::Admin::Users
+end
+
+describe Grape::API do
+  subject { Main }
+
+  def app
+    subject
+  end
+
+  it 'works for unspecified format' do
+    get '/users'
+    expect(last_response.status).to eql 200
+    expect(last_response.content_type).to eql 'application/json'
+  end
+
+  it 'works for specified format' do
+    get '/users.json'
+    expect(last_response.status).to eql 200
+    expect(last_response.content_type).to eql 'application/json'
+  end
+
+  it "doesn't work for format different than specified" do
+    get '/users.txt'
+    expect(last_response.status).to eql 404
+  end
+end
diff --git a/spec/grape/api_spec.rb b/spec/grape/api_spec.rb
index 9973ae7a5f..b678eedf93 100644
--- a/spec/grape/api_spec.rb
+++ b/spec/grape/api_spec.rb
@@ -804,7 +804,8 @@ def subject.enable_root_route!
     it 'sets content type for json error' do
       subject.format :json
       subject.get('/error') { error!('error in json', 500) }
-      get '/error'
+      get '/error.json'
+      expect(last_response.status).to eql 500
       expect(last_response.headers['Content-Type']).to eql 'application/json'
     end
 
@@ -812,6 +813,7 @@ def subject.enable_root_route!
       subject.format :xml
       subject.get('/error') { error!('error in xml', 500) }
       get '/error'
+      expect(last_response.status).to eql 500
       expect(last_response.headers['Content-Type']).to eql 'application/xml'
     end
 
@@ -2642,7 +2644,11 @@ def static
         get '/meaning_of_life'
         expect(last_response.body).to eq({ meaning_of_life: 42 }.to_s)
       end
-      it 'does not accept any extensions' do
+      it 'accepts specified extension' do
+        get '/meaning_of_life.txt'
+        expect(last_response.body).to eq({ meaning_of_life: 42 }.to_s)
+      end
+      it 'does not accept extensions other than specified' do
         get '/meaning_of_life.json'
         expect(last_response.status).to eq(404)
       end
diff --git a/spec/grape/path_spec.rb b/spec/grape/path_spec.rb
index 799fcc2744..f2f93a067d 100644
--- a/spec/grape/path_spec.rb
+++ b/spec/grape/path_spec.rb
@@ -182,11 +182,12 @@ module Grape
 
     describe '#suffix' do
       context 'when using a specific format' do
-        it 'is empty' do
+        it 'accepts specified format' do
           path = Path.new(nil, nil, {})
           allow(path).to receive(:uses_specific_format?) { true }
+          allow(path).to receive(:settings) { { format: :json } }
 
-          expect(path.suffix).to eql('')
+          expect(path.suffix).to eql('(.json)')
         end
       end
 
@@ -237,12 +238,13 @@ module Grape
       end
 
       context 'when using a specific format' do
-        it 'does not have a suffix' do
+        it 'might have a suffix with specified format' do
           path = Path.new(nil, nil, {})
           allow(path).to receive(:path) { '/the/path' }
           allow(path).to receive(:uses_specific_format?) { true }
+          allow(path).to receive(:settings) { { format: :json } }
 
-          expect(path.path_with_suffix).to eql('/the/path')
+          expect(path.path_with_suffix).to eql('/the/path(.json)')
         end
       end
     end