Scott Morrison has been accused of tricking pensioners with misleading claims of an $800 pensioner bonus after confirmation that hardly any seniors will secure that amount.

The New Daily revealed on Tuesday that less than 1 per cent of the one million aged pensioners promised a better deal under changes to the deeming rate will secure the maximum $800 for singles and $1000 for couples.

The changes were the subject of front-page newspaper reports in July heralding a “$800 pensioner bonus”.

But freedom-of-information requests lodged by The New Daily reveal that less than 1 per cent will secure that amount.

Opposition social services spokeswoman Linda Burney said pensioners had every right to feel conned.

“Scott Morrison has been caught out by his own figures,” she said.

“For the vast majority of pensioners, this isn’t enough to buy a cup of coffee. After waiting more than four years for the government to do something about the deeming rates, it’s an absolute slap in the face.

“Pensioners have every right to feel conned. Scott Morrison should not be propping up his budget on the back of pensioners.”

In Parliament, she asked the Morrison government to confirm whether only a fraction of pensioners will secure the maximum amount of $800.

“How can the Prime Minister explain this broken promise?” she asked.

Treasurer Josh Frydenberg responded to the question instead of the PM, stressing the government said that pensioners will receive “up to” that amount.

“I can confirm that under these new deeming rates, affected pensioners will receive up to $40.50 extra a fortnight for couples, which is above $1000,” he said.

“And up to … $31 extra a fortnight for singles, that is $804.

“On average, a couple receiving the aged pension can expect to receive $314 a year extra and a single can expect $250 extra. The cost of these changes to the deeming rates was $600 million to the budget. And it will benefit around one million people.”

Earlier, Social Services Minister Anne Ruston was unable to confirm how many pensioners will secure the maximum $800 amount when questioned at Parliament House.

“It was up to $800, some people will receive … only receive a small amount and ranging up to the maximum amount,” she said.

Asked if the number of pensioners who will secure the maximum amount was less than 1 per cent of the one million eligible, Ms Ruston said it “constantly changes” as investments change, but the figure was “probably correct”.

“At a point in time that probably is correct,” she said.

“It would depend on the amount of cash and assets they are deemed to hold.”

Senator Ruston said she did not accept the claim was misleading.

“Look, I was very clear at the time that the advice I received was that it was $804 for singles and over $1000 for couples. That is correct,” she said.

“It would depend on the amount of cash and assets that the person is deemed to hold.”