The 19th Annual Jane Austen Festival will be held in Bath, England from September 13-22, 2019. The schedule of events has not been finalized but there will probably be music, food, and a ball.
If you are attending, there’s still time to get your costume finished. Costumes are not required.
If you live in North America, you could attend the 11th Annual Jane Austen Festival in Louisville, Kentucky which is held July 12-14. There will be workshops, a children’s tea, an afternoon tea, and a grand ball. It sounds delightful.