Ninety per cent of people want to see continued support for Freeview and broadcast radio, according to a survey.
Research commissioned by telecommunications company Arqiva also indicated 85% of people believe Government or local MPs should actively support its ongoing availability.
Meanwhile, 83% of respondents believed the BBC should continue to actively support these services.
Around three-quarters (73%) said free TV through an aerial is important if not essential, with 84% saying the same of radio.
A quarter of people (25%) said they would feel very lonely if Freeview services through an aerial were lost and a similar proportion (23%) agreed they would be very lonely without radio.
Freeview, the UK’s sole digital terrestrial television platform, is universally available across the country and does not need a superfast broadband connection.
The research is published as the Government and media regulator Ofcom face decisions over the future of UK broadcasting.
Earlier this month, the BBC announced that BBC Four, CBBC and Radio 4 Extra will be moving online only in the coming years.
Current plans only guarantee provision for TV and radio through an aerial until the early 2030s.
In response, Arqiva has launched the Broadcast 2040+ campaign – in collaboration with organisations including Age UK, Silver Voices, the Rural Services Network and the Voice of Listener and Viewer – aiming to safeguard the service until 2040 and beyond.
Shuja Khan, Arqiva’s chief executive, said: “Whether it’s having the radio on over breakfast or watching the news during major global events, TV and radio binds us together as families and communities.
“This national asset cannot be taken for granted and I’m proud of the difference broadcast services make to the lives of people up and down the country.
“People across the UK – including the most vulnerable – depend on content that is available to them at all times, no matter where they live, and doesn’t need a subscription or a superfast internet connection.
“That’s why we’re launching the Broadcast 2040+ campaign in coalition with other groups, to give a voice to viewers and listeners and encourage decision-makers to preserve these critical services for the long-term.”
Charity director of Age UK, Caroline Abrahams, said: “While broadcast TV and radio is enjoyed by many across the UK, it is especially important for older audiences, particularly those on low incomes living alone.
“Many older people value the current universal services and would struggle to afford alternatives such as subscriptions services.
“Watching familiar shows or a public event, such as the recent Jubilee, helps older people feel more connected, giving them a sense of comfort in what can otherwise be an isolating world if you are unable to leave your house easily.
“It’s an important resource and we are happy to support Broadcast 2040+ in its work to protect it.”
Colin Browne, chairman of consumer group Voice of the Listener and Viewer, said: “It is right that everyone in the UK should be able to benefit from the huge potential of broadcasting to inform, engage, and entertain with high quality content.
“And we shouldn’t take our TV and radio services – which are so admired around the world – for granted.
“That’s why we strongly support the Broadcast 2040+ campaign to protect this fundamental national asset for generations to come.
“On behalf of the viewers and listeners who depend on these services, we must ensure that there is a firm commitment to the future of broadcast in the UK.”
Ipsos, on behalf of Arqiva, interviewed a sample of 3,006 participants aged over 18 – 2,005 across Great Britain and a further 1,001 living in postcodes most likely to have been served by the Bilsdale transmitter, between January 26 and March 4.