Hidden updates are updates not announced or mentioned in the Old School RuneScape news or Patch Notes as they might be considered too trivial. These updates are usually minor changes that have no major impact on the game, but they may occasionally be notable and omitted for other reasons.
- On the update of 10 September 2015, splashing was made a much less effective idle training method, as players who did not interact with the client within 15 minutes when in combat would stop retaliating.
- On the update of 10 August 2017, Ugthanki kebab was made darker to distinguish it from regular kebabs.
- On the update of 19 April 2018, the name of an NPC who partakes in the Fight Arena quest was changed from Jeremy Servil to Sammy Servil for unknown reasons.