diff --git a/lib/pleroma/announcement.ex b/lib/pleroma/announcement.ex
index b3c88b441..85500751e 100644
--- a/lib/pleroma/announcement.ex
+++ b/lib/pleroma/announcement.ex
@@ -24,8 +24,7 @@ defmodule Pleroma.Announcement do
 
   def change(struct, params \\ %{}) do
     struct
-    |> validate_params()
-    |> cast(params, [:data])
+    |> cast(validate_params(params), [:data, :starts_at, :ends_at])
     |> validate_required([:data])
   end
 
@@ -39,11 +38,8 @@ defp validate_params(params) do
       Map.merge(base_struct, params.data)
       |> Map.take(["content", "all_day"])
 
-    %{
-      data: merged_data,
-      starts_at: Map.get(params, "starts_at"),
-      ends_at: Map.get(params, "ends_at")
-    }
+    params
+    |> Map.merge(%{data: merged_data})
   end
 
   def add(params) do
@@ -92,9 +88,9 @@ def render_json(announcement, opts \\ []) do
     base = %{
       id: announcement.id,
       content: announcement.data["content"],
-      starts_at: :null,
-      ends_at: :null,
-      all_day: false,
+      starts_at: announcement.starts_at,
+      ends_at: announcement.ends_at,
+      all_day: announcement.data["all_day"],
       published_at: announcement.inserted_at,
       updated_at: announcement.updated_at,
       mentions: [],
diff --git a/lib/pleroma/web/admin_api/controllers/announcement_controller.ex b/lib/pleroma/web/admin_api/controllers/announcement_controller.ex
index 803408057..ad94e2642 100644
--- a/lib/pleroma/web/admin_api/controllers/announcement_controller.ex
+++ b/lib/pleroma/web/admin_api/controllers/announcement_controller.ex
@@ -32,12 +32,15 @@ def show(conn, %{id: id} = _params) do
     end
   end
 
-  def create(%{body_params: %{content: content}} = conn, _params) do
-    add_params = %{
-      data: %{
-        "content" => content
-      }
-    }
+  def create(%{body_params: params} = conn, _params) do
+    data =
+      %{}
+      |> Pleroma.Maps.put_if_present("content", params, &Map.fetch(&1, :content))
+      |> Pleroma.Maps.put_if_present("all_day", params, &Map.fetch(&1, :all_day))
+
+    add_params =
+      params
+      |> Map.merge(%{data: data})
 
     with {:ok, announcement} <- Announcement.add(add_params) do
       render(conn, "show.json", announcement: announcement)
diff --git a/lib/pleroma/web/api_spec/operations/admin/announcement_operation.ex b/lib/pleroma/web/api_spec/operations/admin/announcement_operation.ex
index e4212dd06..8179a0e7b 100644
--- a/lib/pleroma/web/api_spec/operations/admin/announcement_operation.ex
+++ b/lib/pleroma/web/api_spec/operations/admin/announcement_operation.ex
@@ -95,7 +95,10 @@ def create_request do
       type: :object,
       required: [:content],
       properties: %{
-        content: %Schema{type: :string}
+        content: %Schema{type: :string},
+        starts_at: %Schema{type: :string, format: "date-time"},
+        ends_at: %Schema{type: :string, format: "date-time"},
+        all_day: %Schema{type: :boolean}
       }
     }
   end
diff --git a/lib/pleroma/web/api_spec/schemas/announcement.ex b/lib/pleroma/web/api_spec/schemas/announcement.ex
index 433437aac..094fd7c68 100644
--- a/lib/pleroma/web/api_spec/schemas/announcement.ex
+++ b/lib/pleroma/web/api_spec/schemas/announcement.ex
@@ -16,10 +16,14 @@ defmodule Pleroma.Web.ApiSpec.Schemas.Announcement do
       id: FlakeID,
       content: %Schema{type: :string},
       starts_at: %Schema{
-        oneOf: [%Schema{type: :null}, %Schema{type: :string, format: "date-time"}]
+        type: :string,
+        format: "date-time",
+        nullable: true
       },
       ends_at: %Schema{
-        oneOf: [%Schema{type: :null}, %Schema{type: :string, format: "date-time"}]
+        type: :string,
+        format: "date-time",
+        nullable: true
       },
       all_day: %Schema{type: :boolean},
       published_at: %Schema{type: :string, format: "date-time"},
diff --git a/test/pleroma/web/admin_api/controllers/announcement_controller_test.exs b/test/pleroma/web/admin_api/controllers/announcement_controller_test.exs
index d667526c3..5c9d50120 100644
--- a/test/pleroma/web/admin_api/controllers/announcement_controller_test.exs
+++ b/test/pleroma/web/admin_api/controllers/announcement_controller_test.exs
@@ -80,15 +80,29 @@ test "it returns not found for non-existent id", %{conn: conn} do
     test "it creates an announcement", %{conn: conn} do
       content = "test post announcement api"
 
+      now = NaiveDateTime.utc_now() |> NaiveDateTime.truncate(:second)
+      starts_at = NaiveDateTime.add(now, -10, :second)
+      ends_at = NaiveDateTime.add(now, 10, :second)
+
       response =
         conn
         |> put_req_header("content-type", "application/json")
         |> post("/api/v1/pleroma/admin/announcements", %{
-          "content" => content
+          "content" => content,
+          "starts_at" => NaiveDateTime.to_iso8601(starts_at),
+          "ends_at" => NaiveDateTime.to_iso8601(ends_at),
+          "all_day" => true
         })
         |> json_response_and_validate_schema(:ok)
 
-      assert %{"content" => ^content} = response
+      assert %{"content" => ^content, "all_day" => true} = response
+
+      announcement = Pleroma.Announcement.get_by_id(response["id"])
+
+      assert not is_nil(announcement)
+
+      assert NaiveDateTime.compare(announcement.starts_at, starts_at) == :eq
+      assert NaiveDateTime.compare(announcement.ends_at, ends_at) == :eq
     end
   end
 end
diff --git a/test/support/factory.ex b/test/support/factory.ex
index 620102bbb..64b0049ac 100644
--- a/test/support/factory.ex
+++ b/test/support/factory.ex
@@ -630,7 +630,7 @@ def filter_factory do
 
   def announcement_factory(params \\ %{}, data \\ %{}) do
     %Pleroma.Announcement{
-      data: Map.merge(%{"content" => "test announcement"}, data)
+      data: Map.merge(%{"content" => "test announcement", "all_day" => false}, data)
     }
     |> Map.merge(params)
   end