More than 100 staff at City Link's West Drayton transport hub have been made redundant after last-ditch efforts to rescue the parcel company failed.
Administrators announced on New Year's Eve that 2,536 of the firm's 2,727 employees had lost their jobs.
The remaining 371 employees have been retained to deliver those parcels still within the company's network.
Of the 132 full- and part-time staff working at the firm's Heathrow transport hub, in Stockley Close, West Drayton, 112 have lost their jobs.
All affected employees have received letters offering guidance on claiming redundancy pay, administrators said.
Joint administrator Hunter Kelly, of Ernst & Young, said: “It is with regret that we have to announce substantial redundancies at City Link Limited, which ceased accepting new parcels on 24 December 2014. The company endured substantial losses, which ultimately became too great for it to continue as a going concern, and City Link Limited entered administration following an unsuccessful sale process.
“At meetings across City Link Limited’s UK sites on Monday 29 December 2014 and Tuesday 30 December 2014, employees were informed that there would be substantial redundancies as no new business was being taken on. Many of these employees were sent home, and informed that they would shortly receive formal correspondence to confirm their work status.”
The parcel delivery company, which operates 53 depots and three transport hubs across the UK, entered administration on Christmas Eve as a result of 'continued substantial losses'.
Administrators turned down an offer from an unnamed consortium to buy the business, saying the bid 'offered no money up front and significantly undervalued the assets to be acquired.'
Mick Cash, general secretary of trade union RMT, called the decision to reject the offer a 'disgraceful and cynical betrayal that will wreck the lives of our members, many of whom are owed thousands of pounds.'
He added: “RMT does not believe that those pulling the strings had any interest in saving this business and were happy to cut and run, leaving a trail of human misery in their wake. The City Link collapse has blown the lid off the cosy relationship between bandit capitalism and the political elite.
“RMT will continue to advise and represent our members caught in this corporate failure. Those responsible will slink away with their own resources ring-fenced and leaving the taxpayer to pick up the redundancy tab. The City Link Christmas destruction is an act of industrial vandalism that shames our nation while the government looked on and offered nothing but hollow words."
Business secretary Vince Cable had rejected proposals made by RMT to devise a rescue plan for the business or to bail it out.
However, Mr Cable said the government had put measures in place to help the affected staff to find new jobs.
He said: “This is very sad news for the City Link workers and their families at a particularly difficult time of year.
"The government has put arrangements in place to help employees who are made redundant and we stand ready to help.
"City Link employees and self-employed drivers who have their contracts terminated as a result of City Link’s administration will be able to access the government's rapid response service, which draws together local partners such as Jobcentre Plus and the skills bodies to deliver support for each person affected.
"In addition, a Facebook page has been set-up to link-up companies holding suitable vacancies with those who have been made redundant, so if drivers can be redeployed into new jobs in this competitive buoyant market they will be."
