Vanguard, the low-cost US asset manager, has almost doubled the number of investors and assets on its UK retail platform, with millennials making up nearly half of its customers.

The $5.2tn Pennsylvania-headquartered fund manager, which launched its direct-to-consumer platform to much fanfare in May 2017, now has 50,000 customers using the service — up from around 26,000 in June 2018.