Labor's review into its performance at the May 18 federal election has found former leader Bill Shorten's unpopularity contributed to its defeat, but its tax policies did not cost the party victory.

However the report, released on Thursday, found the size and complexity of Labor’s spending announcements, which totalled more than $100 billion, exposed the opposition to a Coalition attack that "fuelled anxieties among insecure, low-income couples in outer-urban and regional Australia".

The review described Bill Shorten as an "unpopular leader" but noted he "led a united party, saw off two Liberal prime ministers and won all three campaign debates". Credit:Alex Ellinghausen

The review, undertaken by former cabinet minister Craig Emerson and former South Australian premier Jay Weatherill, makes 60 findings and 26 recommendations.

It said Labor lost the election because of a "weak strategy" that could not adapt to the change in Liberal leadership, "a cluttered policy agenda" that looked risky and an "unpopular leader".