HM Revenue and Customs has clamped down on scam texts which purport to be from the taxman and may promise cash rebates.
HMRC said it started a pilot project in April 2017 to combat such messages.
Working with partners, the government has used technology to identify fraudulent texts that suggest they are from HMRC and stops them being delivered.
The scheme has brought about a 90% reduction in customer reports around the spoofing of these specific messages, HMRC said.
These types of scam texts may display something like "HMRC" as the sender rather than a phone number to make them appear legitimate.
Fraudsters alleging to be from the tax body make false claims to recipients, such as suggesting they are due a tax rebate.
Messages often include links to websites which harvest personal information or spread malware. This can in turn lead to identity fraud and the theft of people's savings.
HMRC is reminding people it will never contact customers who are due a tax refund by text message or by email.
In the last 12 months, HMRC also said it has initiated the removal of 16,000 malicious websites, meaning even if texts are delivered the phishing website that people are directed to in a text may have already been removed.
"As email and website scams become less effective, fraudsters are increasingly turning to text messages to con taxpayers,” HMRC's director of customer services, Angela MacDonald, said.
"We have made significant progress is cutting down these types of crime, but one of the most effective ways to tackle it is still to help the public spot the tell-tale signs of fraud."