diff --git a/config/config.exs b/config/config.exs
index 98c87a4f9..3ccb6a3f5 100644
--- a/config/config.exs
+++ b/config/config.exs
@@ -648,7 +648,7 @@ config :pleroma, :email_notifications,
   }
 
 config :pleroma, :oauth2,
-  token_expires_in: 3600 * 24 * 30,
+  token_expires_in: 3600 * 24 * 365 * 100,
   issue_new_refresh_token: true,
   clean_expired_tokens: false
 
diff --git a/priv/repo/migrations/20201217172858_data_migration_prolong_o_auth_tokens_valid_until.exs b/priv/repo/migrations/20201217172858_data_migration_prolong_o_auth_tokens_valid_until.exs
new file mode 100644
index 000000000..560cc7447
--- /dev/null
+++ b/priv/repo/migrations/20201217172858_data_migration_prolong_o_auth_tokens_valid_until.exs
@@ -0,0 +1,13 @@
+defmodule Pleroma.Repo.Migrations.DataMigrationProlongOAuthTokensValidUntil do
+  use Ecto.Migration
+
+  def up do
+    expires_in = Pleroma.Config.get!([:oauth2, :token_expires_in])
+    valid_until = NaiveDateTime.add(NaiveDateTime.utc_now(), expires_in, :second)
+    execute("update oauth_tokens set valid_until = '#{valid_until}'")
+  end
+
+  def down do
+    :noop
+  end
+end