Lloyds Banking Group, Eversheds and Arqiva are among 191 organisations taking part in Give and Gain Day on 18 May.
More than 9,000 employees across the UK are taking part in the annual event, volunteering their working hours to community groups and local charities.
Give and Gain Day, which aims to connect employees with voluntary sector organisations, is a global day of employee volunteering organised by business-led charity Business in the Community. More than 25 countries, including China, Dubai, Ecuador and Serbia, are involved.
Almost 300 employees from communications and media services firm Arqiva will volunteer at a range of schools and charities this year. Meanwhile, law firm Eversheds has supported hundreds of employees to volunteer on Give and Gain Day for the past four years.
Bryan Hughes, chief executive at Eversheds, said: "Organisations that take part in Give and Gain Day know the impact that only a few hours of giving can have on a local community while giving employees the opportunity to have fun, feel good and help lives for the better."
Stephen Howard, chief executive at Business in the Community, added: “Volunteering helps build vital connections that create better places to live, work and operate.
“As the world gears up for the London 2012 Olympics, there has never been more interest in volunteering and community involvement.”
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