Broadband Delivery UK contributed £2 million funding while Swindon and Wiltshire Local Enterprise Partnership gave £1 million to the Wiltshire Online programme.
Gigaclear will be responsible for bringing internet speeds of more than 100mbps to more than 5,800 homes in the area.
Joe Frost, business development director at Gigaclear said: “We’re looking forward to partnering with Wiltshire Council. This will revolutionise daily life for so many people in these rural location, putting Wiltshire on the map as one of the best-connected counties in the UK.
“The award of this contract recognises the confidence Wiltshire Council has in our ability to deliver ultrafast broadband across the county.
“It also marks a fantastic milestone for Gigaclear as we continue to expand our pure fibre network across the country.”
Wiltshire Council cabinet member for broadband, John Thomson, said: “Thousands upon thousands of premises are seeing the benefits of an improved broadband service thanks to our programme, and we’re delighted even more will do so soon.
“We’re pleased to be working with Gigaclear to provide this next phase of work which will have a positive impact for householders and businesses alike.
“We are committed to providing an improved broadband service to as much as of the county as possible and will continue to look at all opportunities to help us achieve this.”
Residents can find out more information about Wiltshire Online and how the programme will impact them by visiting wiltshireonline.org