A renewed bid to scrap the GST on tampons has failed in the Senate.
The Greens tried to remove the GST from women's sanitary products by amending government legislation extending the impost to imported goods with a value of less than $1000.
The measure raises $300 million over three years.
Greens senator Larissa Waters said that amount would more than offset the cost of removing the 10 per cent GST from pads and tampons, citing independent costings from the Parliamentary Budget Office showing the states and territories would still be $185 million ahead.
There was no longer a revenue excuse for the "sexist, discriminatory" tax on necessary items, especially given condoms were GST-free.
"When the GST laws were drafted, perhaps there were no women in the room," Senator Waters told parliament on Monday.
"Guys, it's biology, it's not a luxury."
The bid fell well short of the necessary votes, with only Nick Xenophon Team senators supporting the amendment.
Labor said it was sympathetic but the low-value bill was not the way to implement the change.
The overarching legislation - which will lead to GST being charged on online purchases - passed the Senate with a Labor amendment to delay the start date by a year to July 1, 2018.
Labor also successfully added a requirement for a Productivity Commission inquiry into the changes.
The amended bill now returns to the lower house for approval.
