Action Fraud has received more than 1,700 reports in the past two weeks of phishing attempts involving scammers pretending to be from HM Revenue & Customs.
It has now issued a warning to remind people that HMRC will never ask for personal or payment information by text or email.
Action Fraud said: "HMRC will never use texts to tell you about a tax rebate or penalty or ever ask for payment in this way.
"Telephone numbers and text messages can easily be spoofed. You should never trust the number you see on your telephones display.
"If you receive a suspicious cold call, end it immediately."
Last month HMRC warned of a "prolific" new scam which has resulted in vulnerable and elderly people losing thousands of pounds.
The scammers prey on victims by cold calling them and impersonating HMRC members of staff. They tell them that they owe large amounts of tax which they can only pay off through Apple’s iTunes vouchers.
The tax man wrote to the chief executives of major UK retailers urging them to share details of the iTunes phone scam with their staff so they can act as a line of defence.
Victims are told to go to a local shop, buy these vouchers, and then read out the redemption code to the scammer.
The conmen then sell on the codes or purchase high-value products, all at the victim’s expense.
Figures from Action Fraud show that there have been more than 1,500 reports of this scam since 2016.