On 12 November, the division was operationally subordinated to the 11th Guards Army, fighting in the capture of Vilkaviškis and crossing the border of East Prussia near Eydtkuhnen. On 11 January 1945, the 66th was transferred to the operational subordination of the 2nd Guards Army, participating in the capture of Gumbinnen and Wartenstein. It was again transferred to the operational subordination of the 48th Army on 16 February, fighting in the capture of Shlobiten and then Braunsberg on 20 March in the Heiligenbeil Pocket. On 2 April, the 66th was withdrawn to the reserve of the front at Elbing. It was operationally subordinated to the 48th Army on 25 April in the Tolkemit area. For capturing Braunsberg, the 66th was awarded the Order of Kutuzov, 2nd class, on 26 April. Between 28 April and 8 May, it fought in the elimination of the German troops on the Vistula Spit and northwest of Elbing.