The Joseph Smith Papers identifies May 28, 1843 as sealing date for Joseph and Emma Hale Smith.
"Nauvoo Journals, May 1843–June 1844," The Joseph Smith Papers website, accessed August 1, 2022
An entry in shorthand in Joseph Smith’s journal suggests that he and Emma, who had been married civilly in 1827, were sealed for eternity on 28 May 1843. One of his close associates, James Adams, was evidently sealed to his wife the same day, and other trusted friends were sealed to their current spouses over the ensuing months.