The EU's statistics office Eurostat said that 44% of companies in Europe outsource some of their IT functions.
The research found that outsourcing was most common in large companies, 75% of which outsource their IT, compared with 40% of small firms.
Denmark is the country with the most outsourcing, with 76% of its companies outsourcing IT.
Over 100,000 companies were asked if they had used external suppliers in the preceding year to perform ICT functions. The survey covered the EU's 27 member states plus Norway and Iceland.
Part of the reason for the use of outsourcing is likely to be problems recruiting IT workers, a problem particularly acute in large companies. The survey found that 37% of large firms had IT vacancies and 18% of them had hard-to-fill positions.
Overall, though, just 7% of firms had IT vacancies and only 3% had hard-to-fill jobs available.
The same research found that the proportion of firms with internet access and broadband connections had risen to 94% and 77% respectively.
Figures from the commercial world earlier this year demonstrated that demand for outsourcing is growing in Europe. Labour sourcing specialists TPI said earlier this year that the value of the biggest contracts, those over EUR40 million, had increased by 78%.