The new 75ml cans' selling point is that they are half the size of a standard 150ml can, but contain the same amount of product with 28% less packaging.
Unilever also claims the cans result in a 25% smaller carbon footprint than the standard-sized containers.
The cans are being rolled out across Unilever's Sure Women, Dove and Vaseline Intensive range, supported by a £12.8m above-the-line marketing drive including TV.
Unilever believes its marketing activity could shake up a deodorant sector in which aerosols account for 80% of sales.
The new can sizes will initially be rolled out solely across women's products. However, should they prove successful, they will be introduced more broadly.
Unilever believes that as it is the biggest provider in the sector, it is its duty to drive innovation.
Last month, Unilever disclosed that it had achieved the milestone of hitting €50bn (£42bn) in annual sales for the first time, helped by a boost in advertising and promotional spend.Follow @johnreynolds10