diff --git a/docs/api/differences_in_mastoapi_responses.md b/docs/api/differences_in_mastoapi_responses.md
index 7d5be4713..168a13f4e 100644
--- a/docs/api/differences_in_mastoapi_responses.md
+++ b/docs/api/differences_in_mastoapi_responses.md
@@ -25,6 +25,7 @@ Has these additional fields under the `pleroma` object:
 - `in_reply_to_account_acct`: the `acct` property of User entity for replied user (if any)
 - `content`: a map consisting of alternate representations of the `content` property with the key being it's mimetype. Currently the only alternate representation supported is `text/plain`
 - `spoiler_text`: a map consisting of alternate representations of the `spoiler_text` property with the key being it's mimetype. Currently the only alternate representation supported is `text/plain`
+- `expires_on`: a datetime (iso8601) that states when the post will expire (be deleted automatically), or empty if the post won't expire
 
 ## Attachments
 
diff --git a/lib/pleroma/web/mastodon_api/views/status_view.ex b/lib/pleroma/web/mastodon_api/views/status_view.ex
index de9425959..7264dcafb 100644
--- a/lib/pleroma/web/mastodon_api/views/status_view.ex
+++ b/lib/pleroma/web/mastodon_api/views/status_view.ex
@@ -6,6 +6,7 @@ defmodule Pleroma.Web.MastodonAPI.StatusView do
   use Pleroma.Web, :view
 
   alias Pleroma.Activity
+  alias Pleroma.ActivityExpiration
   alias Pleroma.HTML
   alias Pleroma.Object
   alias Pleroma.Repo
@@ -165,6 +166,15 @@ def render("status.json", %{activity: %{data: %{"object" => _object}} = activity
 
     bookmarked = Activity.get_bookmark(activity, opts[:for]) != nil
 
+    client_posted_this_activity = opts[:for] && user.id == opts[:for].id
+
+    expires_at =
+      with true <- client_posted_this_activity,
+           expiration when not is_nil(expiration) <-
+             ActivityExpiration.get_by_activity_id(activity.id) do
+        expiration.scheduled_at
+      end
+
     thread_muted? =
       case activity.thread_muted? do
         thread_muted? when is_boolean(thread_muted?) -> thread_muted?
@@ -262,7 +272,8 @@ def render("status.json", %{activity: %{data: %{"object" => _object}} = activity
         conversation_id: get_context_id(activity),
         in_reply_to_account_acct: reply_to_user && reply_to_user.nickname,
         content: %{"text/plain" => content_plaintext},
-        spoiler_text: %{"text/plain" => summary_plaintext}
+        spoiler_text: %{"text/plain" => summary_plaintext},
+        expires_at: expires_at
       }
     }
   end
diff --git a/test/web/mastodon_api/mastodon_api_controller_test.exs b/test/web/mastodon_api/mastodon_api_controller_test.exs
index 24482a4a2..e59908979 100644
--- a/test/web/mastodon_api/mastodon_api_controller_test.exs
+++ b/test/web/mastodon_api/mastodon_api_controller_test.exs
@@ -166,10 +166,11 @@ test "posting a status", %{conn: conn} do
           "expires_at" => expires_at
         })
 
-      assert %{"id" => fourth_id} = json_response(conn_four, 200)
+      assert fourth_response = %{"id" => fourth_id} = json_response(conn_four, 200)
       assert activity = Activity.get_by_id(fourth_id)
       assert expiration = ActivityExpiration.get_by_activity_id(fourth_id)
       assert expiration.scheduled_at == expires_at
+      assert fourth_response["pleroma"]["expires_at"] == NaiveDateTime.to_iso8601(expires_at)
     end
 
     test "replying to a status", %{conn: conn} do
diff --git a/test/web/mastodon_api/status_view_test.exs b/test/web/mastodon_api/status_view_test.exs
index 3447c5b1f..073c69659 100644
--- a/test/web/mastodon_api/status_view_test.exs
+++ b/test/web/mastodon_api/status_view_test.exs
@@ -133,7 +133,8 @@ test "a note activity" do
         conversation_id: convo_id,
         in_reply_to_account_acct: nil,
         content: %{"text/plain" => HtmlSanitizeEx.strip_tags(object_data["content"])},
-        spoiler_text: %{"text/plain" => HtmlSanitizeEx.strip_tags(object_data["summary"])}
+        spoiler_text: %{"text/plain" => HtmlSanitizeEx.strip_tags(object_data["summary"])},
+        expires_at: nil
       }
     }