The nationwide operation resulted in more than 1,050 foreign nationals being removed from the UK over the same period.
The government said it was “expanding right-to-work checks” into the so-called gig economy “where there are higher levels of illegal migrants seeking work”.
Its £5m crackdown targeted businesses who often rely on casual or temporary workers, including fast food takeaways, beauty salons and car washes.
The Home Office said it aims to “shrink the black economy and penalise rogue employers who ignore immigration rules”.
It highlighted the cases of three businesses – in Kilkeel, in County Down, and Larne and Carnlough, in County Antrim – which were the subject of recent immigration raids.
All three businesses were issued with civil penalty referral notices and the Home Office said they face “hefty fines if found liable”.