The heavy armor and powerful long-range gun gave the Tiger II an advantage against all opposing Western Allied and Soviet tanks attempting to engage it from head on. This was especially true on the Western Front, where neither the British nor U.S. forces had brought heavy tanks into service. Only the British 17 pdr anti-tank gun using APDS shot was theoretically capable of penetrating the front of the Tiger II's turret and nose (lower front hull) at 1,100 and 1,200 yd (1,000 and 1,100 m) respectively.Flanking maneuvers were used against the Tiger II to attempt a shot at the thinner side and rear armor giving a tactical advantage to the Tiger II in most engagements.However, the main armament of the Tiger II was capable of knocking out any Allied tank frontally at ranges exceeding 2.5 kilometres, beyond the effective range of Allied tank guns.
The Tiger II was also present at the Ardennes Offensive of December 1944,the Soviet Vistula–Oder and East Prussian Offensives in January 1945, the German Lake Balaton Offensive in Hungary in March 1945, the Battle of the Seelow Heights in April 1945, and finally the Battle of Berlin at the end of the war.
The 503rd SS Heavy Tank Battalion scored approximately 500 kills in the period from January to April 1945 on the Eastern Front for the loss of 45 King Tigers (most of which were abandoned and destroyed by their own crews after mechanical breakdowns or for lack of fuel).                                                                                                                                          -- Wikipedia