Update: 28 October 2014: While this article was first written in January 2013, these emails are still a menace now, so continue to look out for them. HMRC said this month that almost 75,000 fake emails were reported to it between April and September a 70% increase compared to the same period last year. See our 30 Ways to Stop Scams guide to protect yourself.
Watch out for fake emails promising a tax rebate, which are arriving as the deadline for online tax returns looms.
We've been informed of a spate of fake emails, known as phishing emails, claiming to be from HM Revenue and Customs and promising a tax rebate of £244.79 if you click through the link provided.
But don't click on the link as it's from fraudsters. HMRC says it will only contact you by post.
If you click, you risk it uploading a virus to your computer. Often, these are designed to steal your banking and other sensitive login details.
The email reads: "After the last annual calculation of your fiscal activity we have determined that you are eligible to receive a tax refund of £244.79 GBP."
The scam comes just before the deadline for online self-assessment tax returns on 31 January, when many have tax on their mind. If you miss the deadline you risk a £100 fine.
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What are phishing emails?
Phishing emails are fake emails sent by fraudsters in a bid to steal your bank details and passwords. These regularly look like the real thing, but a bank or financial company will not ask for account details or passwords via email.
Always check the authenticity of the link before you click on it. You can do this by hovering over the link, as this will tell you the real address, or copy and paste the link into a search engine.
A spokesman for HMRC says: "We only ever contact customers who are due a tax refund in writing by post. We dont use telephone calls, emails or external companies.
"Anyone who receives an email claiming to be from HMRC should send it to email@example.com before deleting it permanently."