@jonic wrote:....do I need to file a return in both 2025 and 2026, making 2026 the final year?
You file the final 1041 after the trust terminates which is typically when all assets have been distributed except for a "reasonable amount which is set aside in good faith for the payment of unascertained or contingent liabilities and expenses....".
See https://www.law.cornell.edu/cfr/text/26/1.641(b)-3
