The IT services arm of Deutsche Telekom has suffered as a result of businesses holding back on spending during the recession but the UK business has a good pipeline of deals.
T-systems reported an E11m loss in 2009 compared with an E81m profit in 2008.
Sales were down 5.8% to E8.8bn and the company's reduced the size of its workforce by 1.7% in 2009.
Sam Kingston, UK managing director at T-systems, said that the UK business, which has about 1,000 staff, was beginning to contribute more to the global business.
He was, however, cautious about the year ahead. "People are still very cautious and although they are spending they want more for their pound."
As well as its 1,000 UK workers, T-systems has delivery capabilities offshore in Malaysia and near-shore in Slovakia and the former East Germany.
Its UK customers include BP, Centrica, Volkswagen and Royal Sun Alliance.