The proposed tweaks to the Pension Loans Scheme, which lets older Australians get a voluntary loan to supplement retirement income with local real estate as security, include a guarantee debt owed can't exceed the equity in the secured property.

The new legislation will be introduced to parliament on Thursday.

The other change would let pensioners take two lump-sum advance payments across a year, capped at half of the maximum fortnightly rate across the year.

That equates to $12,580 per year for a single person, or $18,960 for a couple.

The scheme currently lets pensioners top up payments with loans; singles can access $1451, while couples can get $2188.

Social Services Minister Anne Ruston said the changes would let older Australians have more choice when accessing it.

"Around 80 per cent of Australians over the age of 65 are home-owners and the Retirement Income Review has highlighted that drawing on a small portion of home equity can substantially improve the retirement outcomes for senior Australians," she said.

"The No Negative Equity Guarantee will provide peace of mind to retirees by knowing that any debt owed to the government will never exceed the equity in the secured property.

"We want our senior Australians to enjoy greater choice, financial independence and quality of life in their retirement years."

The government will launch a campaign to promote the scheme.

Australian Associated Press