Separately, Vodafone said that, effective October 2018, CEO Colao will be succeeded by Chief Financial Officer Nick Read. He joined Vodafone in 2001 as UK finance director, before serving stints as UK chief commercial officer and UK chief executive. As a result, Read will be named as group chief-executive designate at the telecoms giant's annual general meeting on 27 July - presaging a period of transition at the top. During the decade under his leadership, Vodafone has been transformed from a consumer-focused 2G/3G mobile operator to one of the world's leading converged communications companies with a diverse portfolio including the largest mobile and fixed next-generation network in Europe, a significant worldwide enterprise division, and global leadership in the "Internet of Things".
Read, who was appointed to his current post four years ago, previously ran Vodafone's Africa, Middle East and Pacific region.
Vodafone delivered an attributable profit of €2.5bn, compared to a loss of €6.3bn in 2017 when the company incurred a one-off €4.5bn charge in relation to merging its India business with the country's mobile phone provider Idea Cellular Limited.
Vodafone's chairman, Gerard Kleisterlee, said: "On behalf of the board, I would like to express our gratitude to Vittorio for an outstanding tenure".
Colao was appointed to the role in July 2008, and over 10 years at the helm has diversified Vodafone beyond its roots in consumer mobile to become an global enterprise services provider, establishing a leading position in the internet of things (IoT) as well as embracing 4G and broadband services.
Revenue fell 2.2 per cent to £46.5 billion compared to previous year, due to the deconsolidation of Vodafone Netherlands and fluctuating currency rates.
Organic service revenue was up 1.6%, with fourth quarter growth of 1.4%, showing good momentum in data, fixed/convergence and Enterprise.
The turnaround pointed to a "year of significant operational and strategic achievement and strong financial performance", Colao said.
Earlier this month, Vodafone agreed to buy Liberty Global's cable operations in Germany and Central Europe in a deal valued at €18.4bn.