What the emails look like
While the emails look genuine, complete with HMRC logo and official-style reference numbers, the dubious English ("your fiscal activity") should set alarm bells ringing.
Often, the email addresses look genuine too, often ending in 'hmrc.gov.uk'. Here are some of the reported email addresses used to distribute the tax rebate emails, according to HMRC:
The fake phishing website you click through to can also look genuine, as this example demonstrates.
How you can tell the email is a fake
Simple: HMRC never contacts customers who are due a refund by email. It only ever sends such a letter by post.
So even if the email looks as genuine as this one, it's likely to be a fake.
Similarly, it's worth knowing that HMRC never contacts taxpayers about refunds by telephone, and never uses external companies regarding refunds.
Basically, if it doesn't come in the post from HMRC, it's fake. End of story.
What to do if you receive an email
If you do get an email like this, you should send it to HMRC for investigation before deleting it. Forward all suspicious emails to HMRC at firstname.lastname@example.org.
And if you have reason to believe you have been the victim of an email scam, report the issue to your bank/card issuer as soon as possible.
Get safe online
Remember, phishing emails are common for all sorts of issues. As a rule of thumb, never click on links contained in suspicious emails or open attachments. You can get more help via the Get Safe Online website or read our top 12 tips to keep you safe online. If you use online banking, you may also want to read Online banking: how to stay safe.
If you spot a scam, email us at email@example.com or post it on our Q&A pages.
More on scams and frauds