The age at which people receive a free TV licence could increase to 80, a report said.
The option is one of four which has been put forward in a Frontier Economics report as the BBC prepares to take over the funding of concessionary licences in 2020.
Previously, free licences for over-75s were paid for by the Department of Work and Pensions, but the corporation is expected to lose out on more than £725 million in revenue when it takes on the full cost of providing the concession for elderly viewers in two years' time.
Options listed in the report include not changing the current concession, replacing it with a 50% discount for over-75s, increasing the age threshold to either 77 or 80, or introducing a form of means testing.
In looking at the rationale for increasing the age to 80, the report said: "Individuals aged over 80 are more likely to live alone (49%) than individuals aged 75 and above (41%).
"Therefore, this variant could help to target the concession on those who are most reliant on television for companionship."
A public consultation on the future of the concession, setting out a range of options will be launched in the future, the BBC said.
A spokesman said: "We are grateful to Frontier Economics for their full report. It is clearly the result of careful study and analysis.
"It will help inform the BBC's consultation on the future of the over-75s concession once government stops funding it in 2020.
"There are important issues to consider and we will do nothing without consulting with the public."