@davis_mc , this will generally be come under the "constructive receipt " heading ---- if the amount is in the "mail" over the end of year , it is as if you had received it when mailed. So it will be 2024 income even if you do not get it in your hands before a few days into 2025.. It will generally also be the case if the check gets lost and is replaced say by end of Jan in 2025 , depending on exact facts and circumstances.
Does this make sense ?
