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Background Social jetlag (SJL)—the difference between midsleep point (MSP) on workdays and weekends—is highly prevalent in late-adolescent and young-adult populations, where academic schedules and lifestyle conflict with endogenous circadian timing. Elevated SJL (>2 h) has been linked to poorer sleep quality, reduced daytime functioning, and increased vulnerability, with these effects particularly pronounced in neurodivergent (ND) groups (Coogan & McGowan, Neurosci Biobehav Rev 2017;77:109–33; Baker & Richdale, Sleep Med 2017;36:86–97). UK data on SJL distributions, and on demographic and sleep-related factors associated with them, remain sparse in university students and are entirely absent for NHS staff.Methods Year-2 undergraduate students (n=73, aged 19–34, F/M 44/29) completed a 5–14-day sleep diary. SJL was calculated as the difference between MSP on weekdays (Sun–Thurs) and weekends (Fri–Sat) and categorised into four groups: <0.5, 0.5–1.0, 1.0–2.0, and >2.0 h, where >2.0 h is regarded as clinically relevant misalignment (Wittmann et al., Chronobiol Int 2006;23:497–509). Sleep variables included weekday and weekend MSPs, total sleep time (TST), and sleep efficiency (SE). The total group was subdivided into ND and neurotypical (NT) participants, and SJL was compared between groups. Data were analysed using GraphPad v10.6.1. Data are given as mean (SD); unpaired t-tests compared ND–NT differences and ANOVA compared across SJL groups.Results Table 1 summarises the data. There was no significant difference in TST or SE across SJL groups, whereas MSP on weekdays and weekends differed significantly across groups (p<0.001), but not within each group. 18% of the sample, including 25% of ND and 15% of NT participants, were classified as having high SJL (>2 h).Conclusion Although the present sample did not show statistically reliable ND–NT differences in SJL, 18% of participants experienced >2 h of social jetlag, a level associated with poorer mood, reduced cognitive performance, and increased physiological strain. Given that NHS staff often work irregular or rotating schedules, it is plausible that even greater levels of misalignment may occur in clinical settings, highlighting the need for further research into SJL and wellbeing in healthcare populations.Abstract P25 Table 1Summary of data divided into social jet lag (SJL) groups. Data are presented as mean (SD) for weekdays (Sunday to Thursday) and weekends (Friday to Saturday) in hh:mm for the whole group and subdivided into neurodiverse (ND) and neurotypical (NT) participants. <0.50 is normal, 0.5-1.0 is mildly elevate, 1.0-2.0 is moderately raised SJL and > 2.0 is abnormal/high risk. TST – Total sleep time, SE – sleep efficiency (%) and MSP – mid-sleep point<0.50.5 – 1.01.0 to 2.0>2.0Group (n = 73)24211513TST – weekend08:15 (01:25)08:32 (01:32)07:43 (02:06)09:10 (02:03)TST - weekdays08:05 (01:08)08:06 (01:25)07:55 (01:16)09:07 (01:55)SE – weekend (%)88.5 (6.9)83.8 (11.3)83.3 (14.9)87.3 (8.9)SE – weekdays (%)88.7 (6.7)87.0 (7.3)86.3 (8.8)86.5 (8.3)MSP – weekend04:33 (01:07)04:35 (01:08)06:27 (01:31)07:15 (02:33)MSP – weekdays04:31 (01:05)04:21 (01:12)06:38 (02:40)06:14 (02:35)SJL (hh:mm))00:11 (00:08)00:44 (00:08)01:21 (00:17)03:56 (02:17)ND (n = 20)2855SJL (hh:mm)00:12 (00:06)00:44 (00:08)01:23 (00:20)03:14 (01:00)NT (n = 53)2213108SJL (hh:mm)00:11 (00:08)00:43 (00:08)01:20 (00:16)04:22 (02:49)