diff --git a/elixir/apps/domain/lib/domain/gateways/gateway/changeset.ex b/elixir/apps/domain/lib/domain/gateways/gateway/changeset.ex
index fe54b24f7..5a5723adc 100644
--- a/elixir/apps/domain/lib/domain/gateways/gateway/changeset.ex
+++ b/elixir/apps/domain/lib/domain/gateways/gateway/changeset.ex
@@ -76,7 +76,7 @@ defmodule Domain.Gateways.Gateway.Changeset do
   defp changeset(changeset) do
     changeset
     |> trim_change(:name)
-    |> validate_length(:name, min: 1, max: 256)
+    |> validate_length(:name, min: 1, max: 255)
     |> unique_constraint(:name, name: :gateways_group_id_name_index)
     |> unique_constraint([:public_key])
     |> unique_constraint(:external_id)
diff --git a/elixir/apps/domain/test/domain/gateways_test.exs b/elixir/apps/domain/test/domain/gateways_test.exs
index b975488bc..43730a5e0 100644
--- a/elixir/apps/domain/test/domain/gateways_test.exs
+++ b/elixir/apps/domain/test/domain/gateways_test.exs
@@ -786,7 +786,7 @@ defmodule Domain.GatewaysTest do
       assert {:error, changeset} = update_gateway(gateway, attrs, subject)
 
       assert errors_on(changeset) == %{
-               name: ["should be at most 256 character(s)"]
+               name: ["should be at most 255 character(s)"]
              }
     end