"We have or will exit from seven leases across Europe and the UK. The number of employees affected will be 50 employees from our support services as well as 13 from our sales management," Chief Financial officer Alex Smith told Reuters.
SThree said the restructuring, which would include its property portfolio and support functions, was expected to help save 3 million pounds in the second half of the year and reduce its annualised cost base by 8 million pounds per year.
The staffing company last month reported a lower first-half gross profit as it recruited fewer permanent hires, particularly in the UK and Ireland.
SThree on Monday said it would close four offices in the UK and three in France. It operates 67 offices across the world and employs 2,300 people.
"I think it's fairly substantial. They have an annualised cost base savings of 8 million out of a cost base of 175 million," Numis Securities analyst Steve Woolf told Reuters.
Analysts at Panmure Gordon reduced their 2013 and 2014 profit forecast for the company. The brokerage has a "sell" rating on the stock.
Shares in the company fell 2.6 percent to 346 pence at 09:16 a.m. on Monday on the London Stock Exchange.
(Reporting by Tasim Zahid in Bangalore; Editing by Supriya Kurane)