This is the concept of being legally and automatically signed up to a pension scheme through your workplace, who will contribute towards the employee's pension. This is a government requirement, where the employee and employer combined need to contribute at least 8% of the employee's salary into the workplace pension; the most typical percentages for many employers are 5% employee + 3% employer respectively.

Employees have to actively 'opt out' if they don't want to pay into their pension.
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