The long-term future of more than 800 jobs in Suffolk and north Essex is in doubt under plans to close nearly 140 HM Revenue & Customs offices across the country.

A total of 15 HMRC offices in the East of England are due to close by 2028, to be replaced by a new regional centre based at Stratford, in east London.

The move, part of a national reorganisation which will see around 160 HMRC offices replaced by just 13 regional centres plus four specialist units, was condemned as “devastating” by the Public and Commercial Services Union (PCS) which claimed that 15,000 jobs across the country could be lost as a result.

However, HMRC said the changes would be phased in over a 10-year period in order to minimise redundancies, with most of the targeted £100million in annual savings being achieved through reduced property costs.

Under the proposals, the entire London, South East and East of England region will be covered by just two offices, one in Stratford and the other in Croydon.

HMRC said, nationally, the reorganisation would involve the closure of 137 offices by 2028, with the timings depending on factors including lease breaks.

Among the first offices to close in the East of England, in the 2016-17 financial year, will be those in Colchester, which has a workforce of 90, and Felixstowe, where six people are currently employed.

These jobs will all transfer in the short term to HMRC’s Haven House offices in Lower Brook Street, Ipswich, as will 67 jobs at the Harwich office which is due to close a year later, in 2017-18.

Also to close in 2016-17 is the Chelmsford office, from where the current total of 155 jobs will be relocated to the HMRC office in Southend-on-Sea, which is due to remain open until 2019-20 by which time all jobs there are due to have been transferred to Stratford.

The St Clare’s House office in Ipswich, which has a workforce of 166, is due to close in 2023-24, with these jobs also initially transferring to Haven House. The final move of jobs from Haven House, which has a current workforce of 327, to Stratford is not due to take place until 2027-28.

An HMRC spokeswoman said that staff would have time to consider and discuss their future and that, in cases where they were unwilling or unable to relocate, they could be offered a range of exit options.

However, the PCS called for the HMRC proposals to be subjected to Parliamentary scrutiny, pointing to recent criticism of the organisation by a committee of MPs for “woefully indadequate” efforts to tack tax evasion.

PCS general secretary Mark Serwotka said: “No one should be in any doubt that, if implemented, these proposals would be absolutely devastating for HMRC and the people who work there.

“Closing this many offices would pose a significant threat to the operation of HMRC, its service to the public and the working lives of staff, and the need for parliamentary scrutiny of the plans is undeniable and urgent.”

But Lin Homer, HMRC chief executive, said: “HMRC has too many expensive, isolated and outdated offices. This makes it difficult for us to collaborate, modernise our ways of working, and make the changes we need to transform our service to customers and clamp down further on the minority who try to cheat the system.

“The new regional centres in Stratford and Croydon will bring our staff together in more modern and cost-effective buildings in areas with lower rents. They will also make a big contribution to the economy of the region providing high-quality, skilled jobs and supporting the Government’s commitment to a national recovery that benefits all parts of the UK.”

Frank Haskew of the Institute of Chartered Accountants in England and Wales, said the latestest restructuring would place yet more pressure on an organisation that was already failing to deliver the level of service taxpayers had a right to expect.

“Given the challenge of improving service standards and closing the tax gap, we are concerned that this is the wrong time to be reorganising, closing offices and cutting staff,” he added.