•  Ageing is characterized by changes in circadian rhythms. •  Reduced light exposure or reduced responsiveness to light in older adults may contribute to age‐related circadian changes. •  We hypothesized that the aged circadian clock would exhibit a decreased response to light at a lower intensity (2000 lux) but not to light at a higher intensity (8000 lux). Here, we assessed phase‐shifting responses to 2 h of broad‐spectrum white light at two different intensities in 29 healthy younger and 16 healthy older subjects. •  Older subjects had a significantly earlier phase and lower amplitude of melatonin rhythm compared with younger subjects. •  There was no evidence of age‐related changes in the magnitude or direction of phase shifts of melatonin mid‐point in response to 2 h of broad‐spectrum white light at either 2000 lux or 8000 lux; this indicates that the acute phase‐shifting response to light is not significantly affected by age. Abstract  Age‐related changes in circadian rhythms may contribute to the sleep disruption observed in older adults. A reduction in responsiveness to photic stimuli in the circadian timing system has been hypothesized as a possible reason for the advanced circadian phase in older adults. This project compared phase‐shifting responses to 2 h of broad‐spectrum white light at moderate and high intensities in younger and older adults. Subjects included 29 healthy young (25.1 ± 4.1 years; male to female ratio: 8 : 21) and 16 healthy older (66.5 ± 6.0 years; male to female ratio: 5 : 11) subjects, who participated in two 4‐night and 3‐day laboratory stays, separated by at least 3 weeks. Subjects were randomly assigned to one of three different time‐points, 8 h before (−8), 3 h before (−3) or 3 h after (+3) the core body temperature minimum (CBTmin) measured on the baseline night. For each condition, subjects were exposed in a randomized order to 2 h light pulses of two intensities (2000 lux and 8000 lux) during the two different laboratory stays. Phase shifts were analysed according to the time of melatonin mid‐point on the nights before and after light exposure. Older subjects in this study showed an earlier baseline phase and lower amplitude of melatonin rhythm compared to younger subjects, but there was no evidence of age‐related changes in the magnitude or direction of phase shifts of melatonin mid‐point in response to 2 h of light at either 2000 lux or 8000 lux. These results indicate that the acute phase‐shifting response to moderate‐ or high‐intensity broad spectrum light is not significantly affected by age.