Assalamu alaykum, I sold some stock and borrowed some money from my parents for the down payment on a house. Is this money subject to zakat? I barely have enough for the down payment and closing cost! Note: I will be getting a Sharia-compliant mortgage, insha'Allah. Jazakum Allah khayran.

If one full lunar year has already passed while this money has been in your possession and the total amount (when added to any other wealth you own) has reached the threshold (nisab), then you must pay Zakat on it.