There are 4.6 million people working for themselves, or 15% of the total workforce, the highest number since records began almost 40 years ago.
This compares with 13% of the workforce self-employed at the start of the recession in 2008, according to official data from the Office for National Statistics.
The top three jobs by the number of self employed are blue collar roles. Some 167,000 people are employed in construction and building, 166,000 are taxi drivers and chauffeurs and 144,000 are carpenters and joiners.
Since January 2008, 1.1 million extra people have found work. And of those, 732,000 - or two thirds of the total - define themselves as self-employed.
There has also been a large increase in self-employment amongst managers, directors and senior officials, and amongst management consultants, book-keepers, photographers and chartered accountants.
The rise in self employed people has helped offset the number of people who lost their jobs as the deepest recession in recent UK history took hold six years ago.
However, the average income of self-employed workers has slumped by 22% over the same period, the ONS says. They also tend to work longer hours. The ONS said 35% of self-employed people normally work 45 hours or more a week, compared with 23% of full-time employees.
Frances O'Grady, general secretary of the TUC, said people are finding it difficult to get out of self-employment and into full-time work: 'Self-employment appears to be a key factor in the UK economy’s shift towards low-paid work.'
'The latest assessment of earnings from self-employment is £207 a week, less than half that of employees. They also don’t receive any sick or holiday pay, nor do they have an employer contribute towards their pension,' she added.
How does the UK compare to the rest of Europe when it comes to self employment?