A Holyrood debate will urge ministers to scrap plans which could see council tax hikes of up to 22.5% in some households.
Scottish Liberal Democrat economy spokesman Willie Rennie is set to condemn the proposed sliding scale increases of 7.5% to 22.5% for properties on tax band E or higher.
It comes as a consultation by the Scottish Government and Cosla – the local council governing body – on the plans concludes on Wednesday.
Analysis by the Liberal Democrats suggests 28% of households are set for an additional tax increase on top of any yearly increases, with 715,312 families seeing a hike ranging from £124 to £835, if the plans go ahead.
The rate of the increase could depend on the higher tax band, with those in band E seeing the lowest increases of between £124 to £150.
It is thought that 354,197 households could be affected.
Meanwhile, 14,032 households in the highest H band could see increases of around £694 and £835.
The proposals could raise more than £170 million for local authorities, if passed, it is understood.
Speaking ahead of Tuesday’s debate, Mr Rennie said the Scottish Government’s initial plans to abolish council tax with a fairer system has been abandoned in favour of increases.
He said: “It’s 16 years since the SNP solemnly promised in their manifesto to abolish and replace council tax.
“But after 16 years of consultations, working groups, of cross-party talks, think tanks and rhetoric, the SNP government have transformed from reformers to defenders of the unfair, discredited council tax.
“Now they are hiking it with the biggest rises ever, in the middle of a cost-of-living crisis.
“These tax hikes must be scrapped. The Government should instead back Scottish Liberal Democrat plans that would deliver the power surge which councils need and end the underfunding of local government once and for all.”
Public finance minister Tom Arthur said: “These potential changes to council tax would only affect around a quarter of properties and, even after they are taken into account, average council tax in Scotland would still be less than anywhere else in the UK.
“Many people are struggling with their finances and our council tax reduction scheme is there to ensure nobody has to pay a council tax bill they cannot be expected to afford, regardless of what band they are in.
“I would encourage anyone who has views on these proposals to complete our consultation before it closes on Wednesday, to help us determine if they should be taken forward.”
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