Eve Sleep lost £19million last year on sales of just £27million, the company revealed.
Losses shot up 41 per cent as the online mattress retailer dealt with costs associated with listing on the London Stock Exchange.
Its bottom line was also hit by a significant increase in marketing spend, which soared 119 per cent to £17.2million.
It advertises predominantly on Facebook, Google and television.
Sales at Eve, which sells its products in the UK, Germany and France, jumped 132 per cent to £27.7million.
The firm is one of a new breed of mattress retailers that have become popular in recent months.
Like rivals Simba and Casper, Eve Sleep sells memory-foam mattresses that arrive to customers rolled up inside a cardboard box.
Chief executive Jas Bagniewski said Eve is targeting UK profitability at the end of 2018.
Emily Stella of digital media firm Global Data warned the market was becoming overcrowded.