The workers submitted the collective grievance in April 2025, which contain allegations of bullying by a manager at a Tesco store in Yeading over the course of two years.
However, GMB has said that Tesco is yet to fully investigate the complaint or issue an outcome, while the staff member appointed to hear the grievance is no longer with the business.
As a result, the trade union has requested a written outcome within five working days, citing ACAS guidance which requires that grievances be handled ‘without unreasonable delay’ and Tesco’s own grievance policy, which commits to concluding investigations ‘within a reasonable timeframe’.
Tesco has said in response that it is working with its employees and the union to “resolve this issue”.
The union has also received reports from members that the manager named in the complaint has resumed their inappropriate behaviour and targeted individuals they believe are involved in the grievance.
Trevlyn McLeod, GMB regional organiser, described Tesco’s delay in responding to the grievance as “shameful”.
“It took enormous courage for our members to raise a grievance,” McLeod said.
“This isn’t just a delay – it’s a failure of basic process. Tesco’s failure to act on these bullying allegations risks undermining staff confidence that their concerns will be heard and treated seriously.”
Meanwhile, a Tesco spokesperson said: “We are committed to ensuring that everyone feels welcome at Tesco and there is no place for bullying of any kind in our business.
“We take all allegations extremely seriously, and we work hard to address colleague concerns within a reasonable timeframe. Whilst we are unable to comment on individual cases, we continue to work with colleagues and the trade union GMB to resolve this issue.”
