Ageism is the most common form of discrimination experienced by people in the UK, according to research by Age Concern.
The charity surveyed 2,000 adults and found that 23 per cent of the population had been subject to ageism - representing a figure three times higher than other forms of discrimination.
Of the discrimination, 41 per cent relates to age, which rises to 56 per cent for over 55-year-olds.
"Society too often turns a blind eye to ageism - but our research shows it is actually the most common form of discrimination," said Gordon Lishman, the director general of Age Concern.
"The impact of ageism is also significant. It can mean older people get inferior health care services or are denied access to other goods and services that many take for granted. This blatant discrimination would not be tolerated in any other context."
Older people are being urged to come forward with their experiences of discrimination when trying to access goods and services as part of an Age Concern campaign ahead of the green paper from the discrimination law review in March.
The survey also found that around 7.5 per cent of respondents had suffered sexism, seven per cent racism and six per cent disability prejudice.