OBJECTIVES:  Awareness of real-world biologics dosing patterns in psoriasis (PsO) is limited. This retrospective cohort study assessed dose increase beyond labelled dose and associated pharmacy costs for biologics among moderate to severe PsO patients in the UK. METHODS:  Moderate to severe PsO patients in the UK Hospital Treatment Insights (HTI) database with 1-year wash-out prior to first dispense, who completed induction and were on continued maintenance treatment during 1-year follow-up were included. We used two consecutive maintenance average daily doses ≥30% or ≥10% higher than indicated in the UK Summary of Product Characteristics (SPC) to assess above-label dose and estimated percentage of patients on above-label dose, mean time on above-label dose and extra costs per patient associated with above-label use relative to on-label use of biologics over the 1-year of follow-up period. RESULTS:  The final eligible sample included 362 PsO patients (adalimumab (ADA): 175, etanercept (ETA): 60, ustekinumab (UST): 44, infliximab (INF): 83). Among them, 19% (ADA: 14%, ETA: 20%, UST: 18%, INF: 28%) received ≥30% above-label dose and 33% (ADA: 31%, ETA: 42%, UST: 20%, INF: 39%) received ≥10% above-label dose. The mean days on ≥30% and ≥10% above-label dose were 124 (ADA: 143, ETA: 43, UST: 126, INF: 145) and 118 (ADA: 107, ETA: 57, UST: 153, INF: 176), respectively. The mean extra annual costs per patient with ≥30% above-label dose of ADA, ETA, UST and INF were £7,936, £5,912, £2,422 and £2,275, respectively. The mean extra annual costs per patient with ≥10% above-label dose of ADA, ETA, UST and INF were £5,006, £5,379, £2,491 and £2,578, respectively. CONCLUSIONS:  Dose increase beyond labelled dose is common practice in moderate to severe PsO in the UK. This results into incremental pharmacy costs for payors and underscores the need for fixed dose regimens showing rapid and sustained efficacy for moderate to severe PsO patients.