For a permanent digital copy that includes subtitles, you can purchase the film from:
version over the various English dubs for a more authentic experience Sub vs. Dub: The Viewer Experience Original Subbed Version: The Secret World Of Arrietty Download English Subs
If you need subtitle files ( .srt ) for a legally owned copy (e.g., Japanese Blu-ray without English subs), sites like or Subscene can provide them – but only for personal use with media you own. For a permanent digital copy that includes subtitles,