diff --git a/lib/pleroma/announcement.ex b/lib/pleroma/announcement.ex
index 85500751e..8c15d5bdf 100644
--- a/lib/pleroma/announcement.ex
+++ b/lib/pleroma/announcement.ex
@@ -24,18 +24,20 @@ defmodule Pleroma.Announcement do
 
   def change(struct, params \\ %{}) do
     struct
-    |> cast(validate_params(params), [:data, :starts_at, :ends_at])
+    |> cast(validate_params(struct, params), [:data, :starts_at, :ends_at])
     |> validate_required([:data])
   end
 
-  defp validate_params(params) do
-    base_struct = %{
-      "content" => "",
-      "all_day" => false
-    }
+  defp validate_params(struct, params) do
+    base_data =
+      %{
+        "content" => "",
+        "all_day" => false
+      }
+      |> Map.merge((struct && struct.data) || %{})
 
     merged_data =
-      Map.merge(base_struct, params.data)
+      Map.merge(base_data, params.data)
       |> Map.take(["content", "all_day"])
 
     params
@@ -48,6 +50,12 @@ defmodule Pleroma.Announcement do
     Repo.insert(changeset)
   end
 
+  def update(announcement, params) do
+    changeset = change(announcement, params)
+
+    Repo.update(changeset)
+  end
+
   def list_all do
     __MODULE__
     |> Repo.all()
diff --git a/lib/pleroma/web/admin_api/controllers/announcement_controller.ex b/lib/pleroma/web/admin_api/controllers/announcement_controller.ex
index ad94e2642..6195e582a 100644
--- a/lib/pleroma/web/admin_api/controllers/announcement_controller.ex
+++ b/lib/pleroma/web/admin_api/controllers/announcement_controller.ex
@@ -10,7 +10,7 @@ defmodule Pleroma.Web.AdminAPI.AnnouncementController do
   alias Pleroma.Web.Plugs.OAuthScopesPlug
 
   plug(Pleroma.Web.ApiSpec.CastAndValidate)
-  plug(OAuthScopesPlug, %{scopes: ["admin:write"]} when action in [:create, :delete])
+  plug(OAuthScopesPlug, %{scopes: ["admin:write"]} when action in [:create, :delete, :change])
   plug(OAuthScopesPlug, %{scopes: ["admin:read"]} when action in [:index, :show])
   action_fallback(Pleroma.Web.AdminAPI.FallbackController)
 
@@ -33,16 +33,7 @@ defmodule Pleroma.Web.AdminAPI.AnnouncementController do
   end
 
   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
+    with {:ok, announcement} <- Announcement.add(change_params(params)) do
       render(conn, "show.json", announcement: announcement)
     else
       _ ->
@@ -50,6 +41,30 @@ defmodule Pleroma.Web.AdminAPI.AnnouncementController do
     end
   end
 
+  def change_params(orig_params) do
+    data =
+      %{}
+      |> Pleroma.Maps.put_if_present("content", orig_params, &Map.fetch(&1, :content))
+      |> Pleroma.Maps.put_if_present("all_day", orig_params, &Map.fetch(&1, :all_day))
+
+    orig_params
+    |> Map.merge(%{data: data})
+  end
+
+  def change(%{body_params: params} = conn, %{id: id} = _params) do
+    with announcement <- Announcement.get_by_id(id),
+         {:exists, true} <- {:exists, not is_nil(announcement)},
+         {:ok, announcement} <- Announcement.update(announcement, change_params(params)) do
+      render(conn, "show.json", announcement: announcement)
+    else
+      {:exists, false} ->
+        {:error, :not_found}
+
+      _ ->
+        {:error, 400}
+    end
+  end
+
   def delete(conn, %{id: id} = _params) do
     case Announcement.delete_by_id(id) do
       :ok ->
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 8179a0e7b..cdf04d357 100644
--- a/lib/pleroma/web/api_spec/operations/admin/announcement_operation.ex
+++ b/lib/pleroma/web/api_spec/operations/admin/announcement_operation.ex
@@ -89,17 +89,54 @@ defmodule Pleroma.Web.ApiSpec.Admin.AnnouncementOperation do
     }
   end
 
+  def change_operation do
+    %Operation{
+      tags: ["Announcement managment"],
+      summary: "Change one announcement",
+      operationId: "AdminAPI.AnnouncementController.change",
+      security: [%{"oAuth" => ["admin:write"]}],
+      parameters: [
+        Operation.parameter(
+          :id,
+          :path,
+          :string,
+          "announcement id"
+        )
+        | admin_api_params()
+      ],
+      requestBody: request_body("Parameters", change_request(), required: true),
+      responses: %{
+        200 => Operation.response("Response", "application/json", Announcement),
+        400 => Operation.response("Bad Request", "application/json", ApiError),
+        403 => Operation.response("Forbidden", "application/json", ApiError),
+        404 => Operation.response("Not Found", "application/json", ApiError)
+      }
+    }
+  end
+
+  defp create_or_change_props do
+    %{
+      content: %Schema{type: :string},
+      starts_at: %Schema{type: :string, format: "date-time", nullable: true},
+      ends_at: %Schema{type: :string, format: "date-time", nullable: true},
+      all_day: %Schema{type: :boolean}
+    }
+  end
+
   def create_request do
     %Schema{
       title: "AnnouncementCreateRequest",
       type: :object,
       required: [:content],
-      properties: %{
-        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}
-      }
+      properties: create_or_change_props()
+    }
+  end
+
+  def change_request do
+    %Schema{
+      title: "AnnouncementChangeRequest",
+      type: :object,
+      properties: create_or_change_props()
     }
   end
 
diff --git a/lib/pleroma/web/router.ex b/lib/pleroma/web/router.ex
index 51a9dec6b..af56494a2 100644
--- a/lib/pleroma/web/router.ex
+++ b/lib/pleroma/web/router.ex
@@ -233,6 +233,7 @@ defmodule Pleroma.Web.Router do
     get("/announcements", AnnouncementController, :index)
     post("/announcements", AnnouncementController, :create)
     get("/announcements/:id", AnnouncementController, :show)
+    patch("/announcements/:id", AnnouncementController, :change)
     delete("/announcements/:id", AnnouncementController, :delete)
   end
 
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 5c9d50120..c6b2163d0 100644
--- a/test/pleroma/web/admin_api/controllers/announcement_controller_test.exs
+++ b/test/pleroma/web/admin_api/controllers/announcement_controller_test.exs
@@ -69,13 +69,91 @@ defmodule Pleroma.Web.AdminAPI.AnnouncementControllerTest do
 
       _response =
         conn
-        |> get("/api/v1/pleroma/admin/announcements/#{id}xxx")
+        |> delete("/api/v1/pleroma/admin/announcements/#{id}xxx")
         |> json_response_and_validate_schema(:not_found)
 
       assert %{id: ^id} = Pleroma.Announcement.get_by_id(id)
     end
   end
 
+  describe "PATCH /api/v1/pleroma/admin/announcements/:id" do
+    test "it returns not found for non-existent id", %{conn: conn} do
+      %{id: id} = insert(:announcement)
+
+      _response =
+        conn
+        |> put_req_header("content-type", "application/json")
+        |> patch("/api/v1/pleroma/admin/announcements/#{id}xxx", %{})
+        |> json_response_and_validate_schema(:not_found)
+
+      assert %{id: ^id} = Pleroma.Announcement.get_by_id(id)
+    end
+
+    test "it updates a field", %{conn: conn} do
+      %{id: id} = insert(:announcement)
+
+      now = NaiveDateTime.utc_now() |> NaiveDateTime.truncate(:second)
+      starts_at = NaiveDateTime.add(now, -10, :second)
+
+      _response =
+        conn
+        |> put_req_header("content-type", "application/json")
+        |> patch("/api/v1/pleroma/admin/announcements/#{id}", %{
+          starts_at: NaiveDateTime.to_iso8601(starts_at)
+        })
+        |> json_response_and_validate_schema(:ok)
+
+      new = Pleroma.Announcement.get_by_id(id)
+
+      assert NaiveDateTime.compare(new.starts_at, starts_at) == :eq
+    end
+
+    test "it updates a data field", %{conn: conn} do
+      %{id: id} = announcement = insert(:announcement, data: %{"all_day" => true})
+
+      assert announcement.data["all_day"] == true
+
+      new_content = "new content"
+
+      response =
+        conn
+        |> put_req_header("content-type", "application/json")
+        |> patch("/api/v1/pleroma/admin/announcements/#{id}", %{
+          content: new_content
+        })
+        |> json_response_and_validate_schema(:ok)
+
+      assert response["content"] == new_content
+      assert response["all_day"] == true
+
+      new = Pleroma.Announcement.get_by_id(id)
+
+      assert new.data["content"] == new_content
+      assert new.data["all_day"] == true
+    end
+
+    test "it nullifies a nullable field", %{conn: conn} do
+      now = NaiveDateTime.utc_now() |> NaiveDateTime.truncate(:second)
+      starts_at = NaiveDateTime.add(now, -10, :second)
+
+      %{id: id} = insert(:announcement, starts_at: starts_at)
+
+      response =
+        conn
+        |> put_req_header("content-type", "application/json")
+        |> patch("/api/v1/pleroma/admin/announcements/#{id}", %{
+          starts_at: nil
+        })
+        |> json_response_and_validate_schema(:ok)
+
+      assert response["starts_at"] == nil
+
+      new = Pleroma.Announcement.get_by_id(id)
+
+      assert new.starts_at == nil
+    end
+  end
+
   describe "POST /api/v1/pleroma/admin/announcements" do
     test "it creates an announcement", %{conn: conn} do
       content = "test post announcement api"
diff --git a/test/support/factory.ex b/test/support/factory.ex
index 64b0049ac..d28a56345 100644
--- a/test/support/factory.ex
+++ b/test/support/factory.ex
@@ -628,7 +628,11 @@ defmodule Pleroma.Factory do
     }
   end
 
-  def announcement_factory(params \\ %{}, data \\ %{}) do
+  def announcement_factory(params \\ %{}) do
+    data = Map.get(params, :data, %{})
+
+    {_, params} = Map.pop(params, :data)
+
     %Pleroma.Announcement{
       data: Map.merge(%{"content" => "test announcement", "all_day" => false}, data)
     }