PURPOSE: British Army basic training (BT) and initial trade training (ITT) enable personnel to develop role-related physical capability to perform their job-roles. The aim of this study was to compare the physical performance of separate cohorts of recruits in ITT (who had completed BT) and in-service soldiers, on a series of gym-based fitness tests and role-related representative military tasks (RMTs). METHODS: 316 British Army personnel [68 recruits (63 men, 5 women: 22 ± 3 years, 71.6 ± 8.4 kg, 174.3 ± 7.3 cm), 248 in-service (225 men, 23 women: 27 ± 6 years, 78.7 ± 12.7 kg, 175.9 ± 7.8 cm)] completed two sessions separated by minimum of 48 h. Session 1; body mass, stature and age and seven gym-based tests (2-km run, broad jump, seated medicine ball throw, hex bar deadlift, 100-m shuttle sprints, pull-ups, and isometric mid-thigh pull). Session 2; seven RMTs (load carriage [Stage 1: A = 4 km, 35-40 kg, 4.8 km.h-1, Stage 2: 2 km, 20-25 kg, both to individual timed best effort], tactical movement, water can carry, casualty drag, vertical lift, incremental lift, and repeated carry). Independent sample t-tests were employed with effect sizes reported as Cohen’s D to examine group differences. RESULTS: In-service soldiers were ≈5 years older (p<0.001, d = 1.022), heavier (p<0.001, d = 0.653), and scored higher on the broad jump (p = 0.024, d = 0.312) and seated medicine ball throw (p = 0.007, d = 0.370), but were slower on the 2-km run (p = 0.047, d = 0.282), load carriage (p = 0.019, d = 0.360), tactical movement (p = 0.001, d = 0.476) and casualty drag (p = 0.001, d = 0.656) compared to recruits. No other differences were observed between in-service soldiers and recruits. CONCLUSIONS: This study demonstrates differences in gym-based fitness test and RMT performance between recruits and in-service soldiers. Recruits could perform the role-related RMTs, which suggests that BT provides a sufficient training stimulus. Military Impact: Performance on the gym-based tests and RMTs with the highest aerobic and anaerobic requirement were typically best performed by recruits, suggesting either BT effectively developed these components of fitness, or they decline through a soldier’s career. In contrast, the higher performance on broad jump and seated MBT for in-service soldiers compared to recruits indicate muscle power develops during a service career following BT and ITT. In future these findings could inform development and management of role-related physical fitness during BT, ITT and through career.