He joins the European funds platform hot on the heels of former colleague Stephen Mohan, who took up his position as head of UK and Ireland on 1 October.
The pair worked together at Cofunds where Mohan was managing director, operational services, and Lewis was in a sales role for the institutional market.
Prior to Cofunds, Lewis had a sales and relationship manager position at Euroclear and chaired its UK retail market liaison group.
Allfunds Bank administers £10bn of assets across 20 UK clients in its institutional client base, offering integrated fund solutions – operational, analysis and information.
Created in 2000 and owned by the Santander and Intesa Sanpaolo groups, today Allfunds has more than €100bn assets under administration worldwide and offers close to 35,000 funds from 450 fund managers.
In terms of market coverage, Allfunds Bank has presence in Spain, Italy, UK, Chile, UAE, Luxembourg and Switzerland.