Display omitted •Phenolic acid derivatives (canolol and guaiacol) stabilized linoleic acid-rich oils.•Additive type was more important for oil oxidative stability than its concentration.•Canolol was 4–18 times more effective antioxidant in tested oils than guaiacol.•The lower the initial oil quality, the weaker the protective effect of canolol.•At 100 ppm canolol proved the most efficient, particularly in hemp and poppy oils. Oils high in linoleic acid are the main sources of polyunsaturated fatty acids in the human diet. The study attempted to increase the oxidative stability of 11 cold-pressed oils with various linoleic acid percentages by adding phenolic acid derivatives (canolol, guaiacol) at concentrations of 20–100 ppm. The oils were characterized by acid, peroxide and anisidine values, diene, triene, and water contents, fatty acid composition, and bioactive compounds. Their oxidative stability was evaluated before and after the addition of phenolic acid derivatives in the Rancimat test. The results indicate that both additives can be deployed as antioxidants in linoleic acid-rich oils, but canolol elicits a stronger protective effect (over fourfold). 100 ppm of canolol caused a significant increase in the oxidative stability of most oils (31–79%). The guaiacol effectiveness was greater (13–19% increase) at higher concentrations in hemp and poppy oils, but its lower amounts were more relevant for other oils.