The results are being put down to Green co-leader Metiria Turei's admission of welfare fraud when she was a solo mother - something Little pointed to in his speech to the party's Maori candidates on Sunday as dominating the coverage.
Labour's caucus will meet tomorrow and Little's leadership is likely to be discussed, although Little said his senior MPs had told him they did not believe he should step down and he was adamant he would fight through to the election.
UMR emailed the poll out last week to its clients and it was leaked to Fairfax.
It follows an earlier UMR poll leak the week before which had Labour on 26 per cent.
In the latest UMR poll, National was on 42 per cent and NZ First was at 15 per cent - different results to the Colmar Brunton, which had National on 47 and NZ First on 11.
Newshub this afternoon released part of its latest poll, showing Little's deputy Jacinda Ardern has climbed further as preferred Prime Minister.
That poll has Ardern up almost two points to 8.7 per cent as preferred Prime Minister, while Little is on 7.1 per cent.
National leader Bill English was on 25.8 per cent and NZ First leader Winston Peters on 11.9 per cent - up 2.2 points since the last poll.
Ardern is considered the most likely to replace Little either before or after the election.
She told Newshub Little had her full backing: "There's no plan B, I've given Andrew my absolute support as deputy and I'll keep doing that."
The Newshub Reid-Research poll has Labour on 24.1 per cent - the same as the One News Colmar Brunton poll and just above its result of 23 per cent in a UMR poll taken over a similar period.
Little has revealed he last week raised the prospect of standing down with senior colleagues because of the polls. That was rejected by his senior colleagues but Labour will head into its weekly caucus on Tuesday morning and other MPs will get their say.
The Newshub poll makes it three polls in a row at some of Labour's lowest ever polling levels. The 24.1 per cent was Labour's worse result in the Newshub poll's nine-year history. The main beneficiary appears to have been NZ First, which was up almost 4 points to 13 per cent.
That contrasts with the Colmar Brunton poll which showed a boost for the Green Party while NZ First stayed steady.
The Reid Research poll had National down 2.2 per cent at 45.2 per cent - meaning National would need NZ First to form a Government.
The same poll also showed Little's deputy Jacinda Ardern had climbed further as preferred Prime Minister.
That poll has Ardern up almost two points to 8.7 per cent as preferred Prime Minister, while Little is on 7.1 per cent. National leader Bill English was on 25.8 per cent and NZ First leader Winston Peters on 11.9 per cent - up 2.2 points since the last poll.
Ardern is considered the most likely to replace Little either before or after the election. She told Newshub Little had her full backing: "There's no plan B, I've given Andrew my absolute support as deputy and I'll keep doing that.
"The Newshub Reid Research poll of 1000 voters was taken from July 20-28 and included 750 respondents by telephone and 250 by internet panel. It has a margin of error of +/- 3.1 per cent.