In its introduction, Hitler ordered the new Tigers to be used in the Leningrad siege in September 1942. However, as the faults of the tank were still not yet fully ironed out at this stage, the mechanical unreliability and the unsuitable terrain caused one of the Tiger Is to be stuck in the swamps and abandoned by its users. This example was then captured by the Red Army and tipped off the Allies of the development of the new Tiger tanks and so developments in countermeasures began. In North Africa, the Tigers saw the first action against the Western Allies in Tunisia in December 1942. Its impact there left an impression on the Allied armour forces, but its myth as an invulnerable tank was shattered when two Tigers were taken out by the British 6-pounder anti-tank guns. The total loss in that campaign was seven Tigers by February 1943.

Once mass-numbers of Tiger Is were available, they were employed in heavy tank battalions that were to be deployed in breakthrough operations or counter-attacks. Field experience with the Tiger showed that the Tiger's heavyweight proved a nuisance in operational mobility, an example being that small bridges were unable to support the Tiger tank's weight. An attempt to remedy this was to use a snorkel device so the tank could ford rivers as deep as four meters, however, this system was phased out of later production models for cost-savings. The Tiger suffered reliability problems in all of its service life that impeded its effectiveness and its high fuel usage limited its combat operations. Armour recovery of the vehicle was also terrible as three heavy recovery half-tracks were required to tow the tank away, causing a strain on the German support line to keep the Tiger tanks in running order. Despite that, the Tiger I proved superior in terms of armour and armament against the Allies and created massive losses among their armoured forces, causing many soldiers to keep an eye out for the infamous "Tigers".

The impact the Tiger had on the battlefield as the superior tank at its introduction created fame to the commanders and crew operating this tank, further fueling the Tiger's reputation in the war as a killing machine. Some Tiger units were able to achieve kill ratios up to 10:1, and some even higher. Some notable Tiger aces known were Kurt Knispel (168 tank kills), Otto Carius (150+), Johannes Bölter (139+), and Michael Wittmann (138).

However, as the war progressed and the impact of the Tiger's surprise in Kursk and Italy has dissolved, Allied developments gave forth more capable tanks able to defeat the Tiger I tanks. The Soviets solution was to up-gun their T-34s with an 85 mm gun to make the T-34-85, and the Western Allies with the 76 mm and 17-pounders on the M4 Sherman and Firefly respectively.. The Tiger went as an highly-invulnerable tank design into a simple heavy tank as the war went on, and it was replaced by the more powerful and more heavily armoured Tiger II in 1944. Despite its replacement, many Tiger I models still saw use up until the end of World War II.