The 2017 data was provided to NZME under the Official Information Act.
It showed 25 per cent of elderly at home in the Lakes DHB area felt lonely, slightly up on 22 per cent nationally.
Age Concern runs a national visiting service to address the problem.
In Rotorua, it has 70 accredited volunteers but there is a "much longer list of lonely people," according to manager Rory O'Rourke.
Volunteer co-ordinator Jessica Pickering said: "Often a change in situation, such as injuries, the loss of a spouse, or relocating, will lead to social isolation for the elderly."
Seventy-one-year-old Robin 'Bini' Weatherley is visited weekly by an Age Concern volunteer.
"I would be quite stuck without the visits," she said.
"We have a good relationship. She tells me if she is going away and we talk on the phone instead."
Bini has been diagnosed with depression, and has bad arthritis which prevents her from getting out as much as she would like to.
She raised her grandson but he moved to Auckland last month for work.
"It is just me, my computer, the iPad, the dog, and two cats now," she said.
"People are so busy in their lives these days, minding their own business. I really do not think they have time for anyone else.
"As neighbours, we do not socialise. People just look right through me."
Bini has been married twice; her first husband died aged 39 and she separated from her second husband.
She is originally from Napier and her family is now overseas and in other parts of New Zealand.
"We all text," she said.
Bini said she tried joining a church for a while, for more company.
"I went right off it. I could not be bothered with the politics."
Alan Long, 84 and Connie Long, 94, are visited by 73-year-old Maggie Pryce as part of the Age Concern programme in Rotorua.
"I do it for interest. I see a lot of older or less fortunate people and it helps me too," Maggie said.
Connie said she was close to one woman next door, but "most neighbours do not mix the way they used to".
"The ambulance came to our house and one neighbour checked on us five days later. 'How's the old boy?' they said. It was terrible! If he had died they would have smelled him by then."
She said she always tried to have a laugh to stay bright, but it was hard when so many of her friends were no longer alive.
"I went through a contact list the other day. 'He's dead, she's dead, he's dead,' I said."
Alan and Connie know they would be a lot worse off if they did not have each other.
When Alan was recently put into respite care for two weeks, Connie was alone at home.
"There were days when I got really miserable and depressed. I really missed him. I just tried to catch up on jobs around the house and knitting to distract me," she said.
The couple said there was an "amazing" amount of help available for the elderly.
"The problem is getting the help if you are computer illiterate like us. It is very hard if you do not have a computer or a cellphone," Connie said.
"We are lucky we have Maggie to keep an eye on us or I do not know what we would do," Alan said.
In a written statement, Lakes DHB portfolio manager for health of older people, Vanessa Russell, said loneliness was not uncommon for older people who had lost friends or whose family no longer lived close by.
"The needs assessors in our Lakes Needs Assessment Service Co-ordination are able to look at whether a person wants to participate more in community or social activities and what assistance can be put in place to do this.
"Over the past 10 years in the Lakes DHB area, we have actively focused on the development of a range of services that are aimed at helping people to live at home, until the point when they would be unsafe to do so with the extra support needed."
Ministry of Social Development seniors director, Diane Turner, said the aim was to ensure seniors were "thriving, participating and contributing as full citizens".
She said there was no simple answer to fixing loneliness and isolation.
"A major step will be developing a new Positive Ageing Strategy. We will be starting a nationwide conversation in June on what are the issues and priorities for inclusion in the new strategy."'