To ask Mr Chancellor of the Exchequer, what steps he is taking to ensure that employers use the correct pension classification code and pay their due amount as contributions.

HM Revenue and Customs (HMRC) publishes detailed guidance for employers on the GOV.UK website about National Insurance Contributions category letters.

https://www.gov.uk/national-insurance-rates-letters

All employers with an occupational pension scheme receive a reference number (Employer Contracted-Out Number) from HMRC. This allows the employer to use specific category letters which indicate that they are paying contracted-out contributions when they make their Real Time Information returns to HMRC. There are also automated checks in place to identify if an incorrect category letters has been used and these are then followed-up with the employer.