The majority of firms visited by the Pensions Regulator (TPR) are those which have failed to make the correct pensions contributions for their staff.
The compliance drive marks a return by TPR to larger-scale in-person inspections targeting different areas across the UK, following the lifting of Covid-19 restrictions.
While TPR has continued with urgent ad-hoc inspections on employers suspected of serious breaches, its routine compliance drives was paused in response to social-distancing restrictions.
TPR's head of compliance and enforcement Joe Turner said: "Despite the challenges of the past two years, the majority of employers have continued to meet their responsibilities, including paying contributions in full on time and recognising that automatic enrolment is business as usual.
"But, where we are aware that an employer is failing to do the right thing, we will take action to protect savers - including on-site inspections. This means we could be knocking on the door of an employer in any part of the UK.
"Where an employer fails to meet their automatic-enrolment duties, our priority is to make sure they become compliant. We use our wide-ranging powers to do so, including issuing financial penalties where appropriate."
As well as detecting and confirming non-compliance, the inspections also allow TPR to gather valuable insight into employer behaviour, including identifying common errors. These include administrative errors in respect of ongoing duties.
In most cases, TPR inspectors work on site with firms found to be non-compliant to help get them back on track.
On-site inspections will be carried out across a number of regions and cities throughout the UK in the coming months.
TPR has previously visited employers in all parts of the UK.
As well as carrying out spot check inspections, TPR also detects non-compliance using real-time information data shared by HM Revenue and Customs, alerts from pension schemes, whistle-blowing reports from individuals, and other information and intelligence.
Based on tax legislation at the time of publication. Please be aware that there will have been changes since this was published. Speak to your adviser for the most up to date information.