Taxpayers are waiting longer than ever for HMRC to deal with complaints, despite the tax authority hiring thousands of extra staff in recent years.
New figures show it now takes HMRC an average of 40 days to respond to an initial complaint, leaving many people waiting weeks for answers on issues ranging from tax refunds to penalties.
The time taken by HMRC to address taxpayer grievances has reached its highest level in five years, according to official data obtained through a parliamentary question.
Response times for initial complaints climbed to 40 days during 2025-26, up from 29.6 days in 2021-22.
The decline in performance comes despite HMRC increasing its workforce by around 3,000 employees over the same period.
The number of first-stage complaints has also risen sharply, with approximately 93,600 lodged in 2024-25, compared to 65,600 five years earlier.
Last year, a public accounts committee report concluded that HMRC's customer service had fallen to an all-time low.
Liberal Democrat MP Tom Morrison, who obtained the complaints data, described the figures as "a damning indictment of HMRC's performance."
He pointed to the case of a constituent who is waiting for a tax repayment while also facing a £300 penalty for a tax return she says she was never told to submit.
"She has been told not to expect resolution before July," Mr Morrison said.
The time taken by HMRC to address taxpayer grievances has reached its highest level in five years
| GETTY"Multiply that across thousands of households and businesses nationwide and you start to understand the true cost of this failure."
The MP urged ministers to abandon superficial fixes and instead develop a credible strategy for reforming the tax authority.
Tax professional Tom Minnikin from Forbes Dawson said the findings came as "no surprise."
He noted that HMRC's own delays frequently form the basis of complaints, compounding frustration when those grievances are then poorly handled.
A public accounts committee report concluded that HMRC's customer service had fallen to an all-time low
| GETTYMr Minnikin pointed to a recent unresolved case where a client spent 18 months waiting for a tax refund exceeding £20,000.
When the client complained about the delay, HMRC took six weeks to respond and offered just £150 in compensation, which Mr Minnikin described as "miserly."
Joanne Walker from the Low Income Tax Reform Group noted that HMRC has procedures for reimbursing reasonable expenses and may offer compensatory payments where delays have caused distress.
HMRC defended its record, with a spokesman stating: "Complaints are down this year, and we're committed to resolving those we do receive quickly and efficiently with more staff dedicated to achieving that."
HMRC aims to resolve issues correctly first time but provides an accessible complaints process when problems occur
| GETTYThe tax authority said its figures for 2025-26, covering complaints up to December, showed approximately 7,000 fewer grievances than the corresponding period in the previous year.
The spokesman added: "Our customer service has seen significant improvement with phone wait times now at just over 10 minutes and customer satisfaction at around 80per cent."
Exchequer secretary Dan Tomlinson said HMRC aims to resolve issues correctly first time but provides an accessible complaints process when problems occur.