Q. If someone from one state works in another state, which minhag hamedinah do we follow?
A: Rema, based on the Talmud Yerushalmi, rules that if a worker from one place went to seek employment elsewhere, we follow the minhag hamedinah of the place of employment (C.M. 331:1).
However, if an employer hired someone local to go do work elsewhere, Panim Meiros (2:63) rules that we follow the minhag hamedinah of their place of residence. Igros Moshe (C.M. 2:57) seemingly disputes this and maintains that we follow the minhag hamedinah of where the work was done. (See Casefile for elaboration on this.)
Nonetheless, if the employee worked in his own locale, and just communicated electronically with the other locale, Igros Moshe agrees that we follow the minhag hamedinah of the place where he performed the work.
Of course, this issue itself is subject to minhag hamedinah, so that if the practice is to pay and provide rights based on the official location of the employer, that is binding.
