Havas results lag behind those of rivals Aegis and WPP, which both recently posted impressive double-digit rises in pre-tax profits.
Across its UK business, highlights in the first six months of the year were the performance of its digital and its media agencies, MPG and Arena Media.
Overall, revenues in the six-month period came in at €765m (£677m), up 5% on 2010.
Organic growth was 5.6% on a global basis, but flat in the UK, which recorded revenues of €86m (£76.2m).
David Jones, chief executive of Havas, said: "Havas had a good first half of 2011" and added that it had "delivered solid improvement in profitability".
During the period, Jones was promoted from global chief executive of Havas Worldwide, to overall chief executive of the French advertising group.
Other significant activity in the period included its UK creative agency Euro RSCG launching a search unit.
Havas claimed it had scooped €940m of net new business in the first half of 2011. Global account wins included Dell for creative agency Arnold, Pfizer for healthcare agency Euro RSCG Life and Groupon's digital activity for Euro RSCG Chicago.
Its media operation, Havas Media, was boosted by winning Eurostar across Europe and the Polish Tourism Organisation in the UK and other European markets.
Across its individual regions, growth in Europe was up 1.3% in the first six months. However, Havas' Spanish, French and Greek operations were hit by revenue declines.
Its North American operations reported a strong performance, growing 7.2%, helped by advertising, digital and healthcare communications.
Almost all the major marketing services groups have now revealed their first half financial performance.
WPP remains the largest, with revenues of £4.7bn, up 6.1% year on year, while revenues at Omnicom were $6.6bn (£4.1bn), up 11.4%.
Interpublic's revenues came in at $3.2bn (£2.8bn), up 9%, and Publicis Groupe's at €2.7bn (£2.4bn), up 6.3%.
Aegis revenues, excluding the contribution from its soon to be sold market research arm Synovate, were £519.1m, up 17.9%.
Japanese ad group Dentsu is yet to report its first half results.