Martin Lewis has issued a warning to every worker in the UK, as millions have "turned down a pay rise without realising it".
Anyone aged 22 to around 66, earning £10,000 a year or more, is automatically opted in to a pension scheme.
Auto-enrolment is a rule which says companies must opt in their employees aged 22 to 66ish (state pension age) who earn at least £10,000/year to pay towards a private pension.