Most retailers in EU countries pay pig breeders for their animals’ lean meat percentage, which does not align fully with measures of pork quality (such as colour). In this study, we investigated the effects of season (summer vs. autumn) on finishing pigs’ performance, carcass characteristics, and meat quality parameters in 24 slaughter pigs. Growing performance traits (live weights, average daily weight gain), slaughter values (warm and cold carcass weights, trunk length, fat thickness) and meat quality parameters (pH at 45 min and 24 h postmortem, colour, drip loss, thawing loss, cooking loss, shear force, and meat composition) were recorded. Seasonal differences were more pronounced for the initial age, the number of days in the growing-finishing phase, and the average daily gain. There was also a significant difference in the trunk length between groups, the fat thickness on withers and loin, and also in mean fat thickness. A significant difference was found in the case of pH, total drip loss, and meat colour (L*). The intramuscular fat and collagen content of meat was significantly higher in summer; in contrast, the protein content of meat samples was considerably lower in summer. In conclusion, seasonal effects on finishers’ performance, lean meat values, and several meat quality parameters highlight the importance of more profound seasonal settings of climate control to fulfil the progressively changing quantitative and qualitative requests of pork sector participants from farm to fork.