Radziwiłł Family Fee Tail (Polish: Ordynacja Radziwiłłów, Belarusian: Ардынацыя Радзівілаў) was a fee tail established in the Polish–Lithuanian Commonwealth and owned by the Radziwiłł family.

Three family fee tail estates were established on the basis of an agreement between the three sons of Mikołaj Czarny Radziwiłł on August 16, 1586 in Grodno. The "Nyasvizh Fee Tail" (Ordynacja Nieświeska, Нясвіжская ардынацыя), "Ołyka Fee Tail" (Ordynacja Ołycka) and "Kleck Fee Tail" (Ordynacja Klecka, Клецкая ардынацыя). It was approved by the Sejm in 1589. Ordynat was the title of the principal heir of the Ordynacja.

The family fee tail existed in partitioned Poland and the Second Republic of Poland until the end of World War II. The last ordynat was Prince Leon Władysław Radziwiłł (1888-1956).^[1]

• Fee tail in the Polish–Lithuanian Commonwealth
• Przygodzice Radziwiłł Family Fee Tail
• Zamoyski Family Fee Tail

• T. Zielińska Ordynacje w dawnej Polsce, „Przegląd Historyczny” 1977 z. 1.