A growing row over hybrid working in Whitehall has erupted after allegations that civil servants are faking office attendance while working remotely, with some staff reportedly going years without physically turning up to work. An investigation has exposed claims from whistleblowers that staff are routinely sidestepping rules requiring a minimum of three days in the office, while managers are said to have "no control" over remote workers. One insider described offices on Fridays as "like the Mary Celeste".

At HM Revenue and Customs, staff are alleged to have gamed attendance systems by connecting to office Wi-Fi from nearby car parks before heading home. Senior managers are reported to refer to the practice as "drive-by login". Internal data shows significant gaps in attendance at HMRC. It found 3,195 staff had not been into an office for between six and 11 months, 992 had not attended for 12 to 23 months, and 182 had not been seen in person for two years or more. HMRC employs more than 70,500 people.

The department said some absences related to sickness, disability adjustments and alternative working patterns.

But one civil servant told The Daily Telegraph that in practice office attendance was often tokenistic. He said: "It's common for a lot of people to be in for a couple of hours and disappear," adding that staff would still be recorded as attending for the day.

Another HMRC whistleblower said remote working habits had hardened since the pandemic, explaining: "You can go years at a time without seeing certain colleagues," he said.

Concerns over productivity have been compounded by wider performance issues across government departments. HMRC has faced criticism for long call waiting times, with almost 44,000 taxpayers cut off after being on hold for more than an hour last year, according to a parliamentary report.

At the Land Registry, 200 staff have not been into the office for more than six months, including 131 absent for over a year and 78 for more than two years. The agency is currently dealing with severe backlogs, with some services delayed by up to 18 months.

The Office for National Statistics has also faced scrutiny over extremely low attendance rates in some offices, with figures in one week showing levels as low as 9%.

Union leaders have argued for continued flexibility, while critics say standards have collapsed since Covid-era working patterns became entrenched.

A government spokesman said a minimum 60% office attendance policy remained in place and insisted the figures represented only a minority of staff, including those on leave or working in alternative roles. Managers, they added, had authority to take disciplinary action where necessary.