People who have sold properties that are not their main homes, and have not told HM Revenue and Customs (HMRC) about any profit on the sale, have one week left to pay up.
HMRC's Property Sales Campaign is aimed at those who have sold second homes in the UK or abroad where capital gains tax (CGT) should be paid. It includes properties that have been rented out and holiday homes.
Taxpayers have until 6 September to pay the tax that they owe. By using the campaign to come forward voluntarily, they will receive the best possible terms, and any penalty will be lower than if HMRC approaches them first.
Marian Wilson, head of HMRC campaigns, said: "Hundreds of people have come forward to take advantage of this campaign. It is not too late to contact us.
"If you have sold a second home you might not know it could attract capital gains tax. You should look at HMRC's website to find out if you owe CGT. Telling HMRC about your tax liabilities is straightforward and help, advice and support are available."
After 6 September, HMRC will take a much closer look at the tax affairs of people who have sold properties other than their main home, but who appear to have paid no CGT. The department will use information that it holds about property sales in the UK - and abroad - to identify people who have not paid what they owe. Penalties - or even criminal prosecution - could follow.
For more details on the campaign, taxpayers can visit HMRC's website: hmrc.gov.uk/campaigns/psc.htm.
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