diff --git a/app/lib/api_tchap/api.rb b/app/lib/api_tchap/api.rb
new file mode 100644
index 000000000..0dec71d53
--- /dev/null
+++ b/app/lib/api_tchap/api.rb
@@ -0,0 +1,22 @@
+class APITchap::API
+  class ResourceNotFound < StandardError
+  end
+
+  def self.get_hs(email)
+    call([API_TCHAP_URL, "info?medium=email&address=#{email}"].join('/'))
+  end
+
+  private
+
+  def self.call(url)
+    response = Typhoeus.get(url)
+
+    if response.success?
+      response.body
+    else
+      message = response.code == 0 ? response.return_message : response.code.to_s
+      Rails.logger.error "[APITchap] Error on #{url}: #{message}"
+      raise ResourceNotFound
+    end
+  end
+end
diff --git a/app/lib/api_tchap/hs_adapter.rb b/app/lib/api_tchap/hs_adapter.rb
new file mode 100644
index 000000000..cdf2aced2
--- /dev/null
+++ b/app/lib/api_tchap/hs_adapter.rb
@@ -0,0 +1,15 @@
+class APITchap::HsAdapter
+  def initialize(email)
+    @email = email
+  end
+
+  def to_hs
+    data_source[:hs]
+  end
+
+  private
+
+  def data_source
+    @data_source ||= JSON.parse(APITchap::API.get_hs(@email), symbolize_names: true)
+  end
+end
diff --git a/config/initializers/02_urls.rb b/config/initializers/02_urls.rb
index 12b2d2e2e..c238ade67 100644
--- a/config/initializers/02_urls.rb
+++ b/config/initializers/02_urls.rb
@@ -5,6 +5,7 @@ API_ENTREPRISE_URL = ENV.fetch("API_ENTREPRISE_URL", "https://entreprise.api.gou
 API_EDUCATION_URL = ENV.fetch("API_EDUCATION_URL", "https://data.education.gouv.fr/api/records/1.0")
 API_GEO_URL = ENV.fetch("API_GEO_URL", "https://geo.api.gouv.fr")
 API_PARTICULIER_URL = ENV.fetch("API_PARTICULIER_URL", "https://particulier.api.gouv.fr/api")
+API_TCHAP_URL = ENV.fetch("API_TCHAP_URL", "https://matrix.agent.tchap.gouv.fr/_matrix/identity/api/v1")
 HELPSCOUT_API_URL = ENV.fetch("HELPSCOUT_API_URL", "https://api.helpscout.net/v2")
 PIPEDRIVE_API_URL = ENV.fetch("PIPEDRIVE_API_URL", "https://api.pipedrive.com/v1")
 SENDINBLUE_API_URL = ENV.fetch("SENDINBLUE_API_URL", "https://in-automate.sendinblue.com/api/v2")
diff --git a/spec/lib/api_tchap/hs_adapter_spec.rb b/spec/lib/api_tchap/hs_adapter_spec.rb
new file mode 100644
index 000000000..082435d9c
--- /dev/null
+++ b/spec/lib/api_tchap/hs_adapter_spec.rb
@@ -0,0 +1,19 @@
+describe APITchap::HsAdapter do
+  let(:adapter) { described_class.new(email) }
+  let(:email) { "louise@mjc.gouv.fr" }
+  subject { adapter.to_hs }
+
+  before do
+    stub_request(:get, /https:\/\/matrix.agent.tchap.gouv.fr\/_matrix\/identity\/api\/v1\/info\?address=#{email}&medium=email/)
+      .to_return(body: body, status: status)
+  end
+
+  context 'with normal body' do
+    let(:body) { "{\"hs\": \"agent.educpop.gouv.fr\" }" }
+    let(:status) { 200 }
+    it 'returns hs' do
+      subject
+      expect(subject).to eq "agent.educpop.gouv.fr"
+    end
+  end
+end