Merry Christmas - you're fired. It's the holiday season, and with corporate gimmicks like Black Friday and Cyber Monday upon us, workers are being exploited through unfair contracts by some of the biggest companies in the UK. 

Tesco, Sainsburys, Argos and dozens of other big firms are using thousands of temp and casual workers to boost their profits. It's a particular issue in the run up to Christmas, but it's a serious worry for millions of workers all year round.

So-called flexible contracts cover workers up and down the country, from Deliveroo's 'independent suppliers', Amazon's 'self-employed' warehouse teams, and Tesco's agency staff. These huge companies don't employ their workers directly, so they can avoid paying pensions, tax and sick pay. 

Tesco, Sainsburys, Argos - End the casual contract scandal in your companies

Workers are so worried about their conditions that over 10,000 people called the ACAS low pay helpline. The long hours they are forced to work to meet targets means that they may fall below the statutory minimum wage, particularly when travel is factored in. 

In other European countries the same companies don't use these 'flexible' contracts, and instead treat their workers properly. But the UK allows this exploitation for the benefit of big business, and even worse the Government encourages it. 

'Flexible' contracts don't always mean low pay, but all too often it does, with zero hours workers earning less than half that of a permanent employee. People can't survive on poverty wages. 

It's also bad for the country as a whole. Some companies use temp agencies to avoid having to pay national insurance, but unbelievably these temp agencies are avoiding tax. We're losing out twice on corporate tax at a time when crucial services like the NHS desperately need money.

SumOfUs members have come together before and forced change on big business many times. Recently, over 60,000 of us signed a petition to get BHS pensions funded properly, and now the Pensions Regulator is looking to enforce against the company's scandal-hit former owner. We've also helped to pressure companies like Apple and T-Movile to make sure they workers get a fair deal.

Tell these exploiting companies we are watching them - sign the petition so they are forced to treat their employees properly

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