The move will affect around 750 Unilever employees across 20 countries. A Unilever representative said that employees were told about upcoming changes a week ago and that over the next two years of implementation, steps will be taken to try to prevent layoffs.
The value of the contract has not been disclosed but was referred to as a "multimillion-euro" deal in one e-mail from the companies.
IBM Business Consulting Services will use sites in India, Poland and Portugal to handle Unilever's purchase-to-pay, general accounting and bill-to-cash functions.
IBM is one of Unilever's key technology partners. Others include BT Group, Hewlett-Packard, Microsoft, Oracle and SAP.
"We looked at the market and the obvious alternatives, but selected IBM as the single provider," a representative of the consumer goods giant told Silicon.com.
Tony Hallett of Silicon.com reported from London.