EXTENDING the completion date for Scotland’s census by four weeks will cost the Scottish Government up to £10 million of extra funding, an SNP minister has confirmed.

The date for Scots to complete the legal requirement or face a £1,000 fine has been pushed back from May 1 until the end of the month, with more than 600,000 households still to complete it.

SNP Constitution Secretary Angus Robertson told MSPs that the four week delay will cost up to £9.7 million.

Mr Robertson said that so far, 77.2 per cent of Scottish households have completed the census, which he labelled “a substantial figure”.

He added: “However, I cannot stress enough how important it is for the government to hear the voices of the remaining 604,000 who are still to return before the deadline of Sunday, May 1.

“That figure also includes many thousands of people who have begun the census online, but haven’t yet completed it, and the thousands of others who have requested a paper copy, but have not yet returned it.”

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The minister confirmed that “National Records of Scotland will now continue to accept census returns until the end of May”.

He said: “In support of this, we will provide an additional budget investment this year of up to 7% that amounts to £9.76 million - of the programme costs. This will allow the census collection period to continue for four weeks to give everybody the opportunity to complete Scotland’s Census, and allow all outstanding returns to be captured so that everyone’s voice can be heard.

“To be effective, a census requires a high response rate and one that captures the diversity of our communities and their needs appropriately. I would like to reassure members that this is a valuable further investment - research shows that for every £1 or equivalent invested in a census it generates £5 to £6 of broader economic benefit.”

Scottish Conservative shadow constitution secretary, Donald Cameron, warned that the handling of the census “has been nothing short of disastrous”.

He added: “It was needlessly delayed by a year and has ended up costing taxpayers an extra £30 million. Almost a quarter of households have still not completed it ahead of the SNP’s initial deadline.

“The SNP ignored Scottish Conservative calls to run the census in sync with the rest of the United Kingdom. They would have clearly benefitted from a UK-wide publicity campaign, which delivered an extremely high response rate elsewhere.

“Despite those warnings, the SNP insisted on going it alone and claimed this would ensure the highest possible response rate. Now we see the exact opposite has occurred.

“Everything about this census response represents a significant failure from the SNP Government, which will have serious, long-term implications for public policy making.”

Scottish Liberal Democrat MSP Willie Rennie said: “From the decision to decouple the timing of the census from the one conducted in England and Wales to difficulties accessing the census online and controversy over how questions were phrased, ministers seem to have gone out of their way to make it as confusing as possible.

“This matters because an accurate census helps to inform the delivery of public services for the next decade. We need urgent action from the government to ensure that the data gap is closed.”