More than six in 10 people in the UK aged 65 or over have experienced depression and anxiety, data shows.
Of these, more than half did not seek help because they thought “they should just get on with it”.
Nearly a quarter relied on support from friends or family.
NHS England and Age UK have launched a campaign to encourage older people to access treatment for mental health conditions.
The survey by the charity found just 13% of over-65s would put their mental health before their physical health.
It suggested ingrained attitudes towards mental health are a possible factor in preventing older people from seeking help for emotional problems.
Alistair Burns, national clinical director for dementia and older people’s mental health at NHS England and NHS Improvement said older people sometimes feel they have to have a stiff upper lip towards health, whereas seeking help is a sign of strength not weakness.
“We should remember that loneliness and isolation can be linked to physical health problems, so getting support through a talking therapist is good for mind and body,” he added.
Caroline Abrahams, Age UK director, said in recent years there has been a cultural revolution in people’s willingness to be open about mental ill-health, but this may have left many older people behind.
“They grew up in an era when there was a real stigma associated with mental illness, so for many, these attitudes are deeply engrained and still driving their behaviour today,” she explained. “A further barrier to seeking support is a widespread lack of awareness about the effective treatments that are available, beyond ‘taking pills’, which many older people feel they do quite enough of already.”