The Humax box delivers content from broadcasters including BBC, Channel 4, ITV and Channel 5 via the internet, eliminating the need for a television subscription.
Users who live outside of Infinity-ready areas can take advantage of the offer on a BT Broadband or BT Vision Essential account, which starts at £5 per month for a minimum of 12 months.
YouView also offers catch-up services, on-demand programming, access to the BT Vision service, and 500Gb hard drive space. Although the Humax box is free of charge, customers are still required to pay a £49 activation charge plus delivery costs.
BT director Alex Green, said: "This is a fantastic offer. Customers will now be able to enjoy BT's super-fast fibre broadband with a YouView box and TV Essential pack all for £18 per month.
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"With YouView from BT not only can customers experience a great new way to watch TV they will also be able to access a huge range of on-demand content from BT Vision. The launch of YouView from BT is another piece of exciting news about BT's plans for TV."
The YouView hardware is not yet available, but customers who register their interest now will be placed at the front of the queue to make their orders between October 19 and 26.
Existing BT Infinity subscribers can upgrade to YouView for £49 plus a £7 delivery fee.