Despite costing more than a Vickers gun to manufacture (the cost of a Lewis gun was £165 in 1915 and £175 in 1918; the Vickers cost about £100), Lewis machine guns were in high demand with the British military during the First World War.
Selv om de var dyrere end et Vickers maskingevær at fremstille (I 1915 kostede et Lewis maskingevær £165, ment et Vickers kostede omkring £100), var Lewis maskingeværer stærkt efterspurgt af det britiske militær under 1. verdenskrig.