Old cats (>10 years) had significantly higher SBP, heart rate, murmur frequency, thrombocyte count, urine protein:creatinine ratio and serum urea and bilirubin concentrations, and significantly lower body condition score, haematocrit, albumin and total calcium concentrations than middle-aged cats (6-10 years). The common occurrence of physical examination and laboratory abnormalities in apparently healthy old cats underlines the need for regular health checks and the development of age-dependent laboratory reference intervals.