Prime Minister Boris Johnson has topped a list of MPs for outside earnings last year, raking in an additional £1.6m on top of his Westminster salary.
In total, MPs made an extra £13m in employment, gifts and property income between 1 September 2018 to 31 August 2019, according to a tool created by data design specialists Set Reset.
Conservatives are the top earners, with 81 per cent pocketing more than their parliamentary salary, working out at an average of nearly £5,800.
But in total 495 MPs registered additional income on top of their day-to-day salary.
Paid employment totalled £5.5m, of which nearly £900,000 came from speaking engagements.
The findings come as Labour ratchets up its pledge to ban MPs from holding paid second jobs, with limited exemptions to maintain professional registrations like nurses.
Labour has also pledged to overhaul rules regulation lobbying and political donations, banning non-doms from being able to make donations, preventing the use of shell companies and introducing a new lobbying register.