After teasing the launch earlier in the month, BT went live with the first of its 5G mobile plans on Friday 11 October.

Piggybacking on EE's infrastructure, BT's 5G network is available in nine UK cities and towns including London, Birmingham, Cardiff, Manchester, Edinburgh, Belfast, Coventry, Leicester and Bristol, yet within this it's actually available in 23 locations.

In the West Midlands, EE is rolling out coverage around Solihull, Dudley, Sutton Coldfield, West Bromwich, and Lichfield. Around Greater Manchester, 5G is being brought to areas around Salford, Oldham, Ashton-under-Lyne, Rochdale and Milnrow. Spreading out from London, EE is launching 5G in Kingston-upon-Thames, Grays, Romford, Chatham and Gillingham.

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This 5G service is supported by the EE's 4G network, as well as BT's Wi-Fi  hotspot network.

The launch makes BT the third provider in the UK to join the 5G smartphone fray, behind Vodafone and its own EE network – the network BT bought back in 2016 – and, with EE, makes the wider company the leading operator when it comes to the number of locations at which 5G speeds are available.

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Existing BT Plus and BT Business customers will be the first to benefit from the option to upgrade to the firm's 5G service, with speeds being quoted in the region of "around 100-150Mbps, even in the busiest of places". BT's 5G plans will then be made more widely available as the service rolls out to a further 25 towns and cities by the end of the year.

BT Plus customers can choose from a 12GB, 30GB, 60GB or 200GB 5G handset plan, starting from £45 per month, which includes the BT Sport app for no extra cost. They will also be able to choose from the list of best 5G phones including:

Samsung Galaxy Note 10+ 5G

Samsung Galaxy S10 5G

OnePlus 7 Pro 5G

OPPO Reno 5G

Huawei Mate 20 X

BT Business customers can choose from 6GB, 30GB, or 60GB 5G mobile plans, plus a £10 discount on their handset or SIM-only plans when they order together with BT Business Broadband. These business plans start at £35 per month for a handset plan, or £15 per month for a SIM-only one. Both include unlimited calls and texts, as well as unlimited access to BT’s 5.5m Wi-Fi hotspots across the UK.

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"Our 5G service provides customers with a faster and more reliable connection in high demand, crowded areas across the UK at peak times," said Marc Allera, CEO of BT’s Consumer Division.

BT Plus is the UK’s first converged fibre and mobile plan and comes with BT’s Keep Connected Promise. If a BT Plus customer reports a fault with their home broadband, BT will switch on free, unlimited data on their BT mobiles within an hour and will also send a free 4G Wi-Fi Mini Hub to arrive the next day, with unlimited data to keep customers connected at home while their broadband is repaired. BT Plus customers also benefit from 24/7 dedicated UK and Ireland support.

BT also announced that customers of its 5G and Plus service will be upgraded to its new "convergence" service, called Halo, which is set to launch in November.

Halo will combine 5G, home phone and broadband in one and BT says it is the first company in the UK to offer such a service. BT Halo will offer customers not only unlimited 5G data, calls and texts but also unlimited home broadband and phone calls.

The Halo plan will replace the current consumer 200G plan, and customers already on this plan will be moved over to unlimited at no extra cost or additional contract length. Further detail on Halo from BT will be announced in November.

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Tacked onto the 5G announcement were a slew of smaller announcements, the most interesting of which is that BT is pledging to upgrade 700,000 homes and businesses to fibre broadband at no extra cost by the summer of 2020. The move could see customers’ broadband speeds leap by a factor of ten, BT says.