Different Lactobacillus collinoides and Brettanomyces/Dekkera anomala cider strains were studied for their ability to produce volatile phenols in synthetic medium. All strains were able to produce 4-ethylcatechol (4-EC), 4-ethylphenol (4-EP) and 4-ethylguaiacol (4-EG) from caffeic, p-coumaric and ferulic acids, respectively. Interestingly, D. anomala and L. collinoides were also able to produce 4-EC, 4-EP and 4-EG in cider conditions. The quantities of ethylphenols produced by these two species were similar in both tested ciders. The impact of precursor quantities was studied and it showed that the addition of caffeic and p-coumaric acids in ciders allowed for higher 4-EC and 4-EP production by D. anomala and L. collinoides. In parallel, D. anomala and L. collinoides strains were isolated from a phenolic off-flavour defective bottled cider after ethylphenol production hence confirming the implication of these two species in this cider spoilage. Finally, detection thresholds of the main ethylphenols were determined in ciders by orthonasal and retronasal sampling. The 4-EC and 4-EP detection thresholds (close to 20–25 mg/l and 1.5–2.0 mg/l, respectively) were matrix dependant. ► All the tested L. collinoides and D. anomala cider strains were able to produce ethylphenols. ► Interestingly, D. anomala and L. collinoides were able to produce 4-EC, 4-EP and 4-EG in real cider conditions. ► Impact of precursor quantities to volatile phenol production was studied in ciders. ► D. anomala and L. collinoides strains were isolated from a bottled cider during ethylphenol production. ► Detection thresholds of the main ethylphenols were determined in ciders by two different methods.