About £10m of the fund, launched by the Department for Work and Pensions last week, was awarded to voluntary organisations.
Of the 740 organisations from voluntary and statutory sectors that applied for funding, 170 were successful.
The RNIB, the RNID, Carers UK and DeafBlind UK received national grants, while their local branches were among the plethora of charities, including Citizens Advice and Age Concern, to be selected locally for two-year funding.
"The new fund will allow a mighty coalition of organisations to deliver extra help to hard-pressed pensioners," pensions minister Malcolm Wicks said at last week's launch of the initiative.
The RNIB ran a pilot scheme in 2003 that identified £150,000 in previously unclaimed benefits for blind and partially sighted pensioners in Nottinghamshire.
RNIB spokesman Bill Alker estimated the £100,000 the charity had received this time would result in a tenfold increase in benefit claims by the people it helps.
"On far too many occasions, blind and partially sighted older people often fail to claim benefits that they are entitled to, because they can't see well enough to read a claim form," he said.
The successful organisations will receive an average of £76,000 over the next two years. The Department for the Environment, Food and Rural Affairs contributed £1.73m to the fund for organisations in rural areas.
- Department for Work and Pensions has set up a £13m fund to help older people claim their benefit entitlement
- £10m has been awarded to voluntary organisations. RNIB, RNID, Carers UK and DeafBlind UK received national grants
- Local RNIB pilot scheme identified £150,000 in unclaimed benefits.