Spontaneous hepatic rupture, secondary to the accumulation of hepatic amyloid, was diagnosed in six cats over a two-year period. Previous reports of feline hepatic amyloidosis have documented clusters of cases from breeding catteries. Most affected cats have been Siamese or a related breed and the disease is generally regarded as familial. In contrast, the cases presented here were sporadic, with relatives and other cats in the household not clinically affected. They included a Devon rex, a breed not previously reported with this condition, and a domestic shorthair. Clinical signs in three of these cases had, prior to referral, been misinterpreted as resulting from blunt trauma, immune-mediated haemolysis or a coagulopathy. Antemortem diagnostic features, including new data on the value of hepatic ultrasonography and fine-needle aspirate cytology, are reported. These cases illustrate how the course of this disease can vary between individuals and that, despite the dramatic underlying pathology, hepatic amyloidosis can present a diagnostic challenge and should be suspected in any young adult cat with consistent clinical signs, irrespective of breed or environment.