Deutsche Telekom beat expectations with an 11 percent rise in quarterly profit helped by its US operations and the weak euro.
Earnings before interest, tax, depreciation and amortisation (EBITDA) excluding special items rose to 4.57 billion euros ($5.15 billion).
That topped an average forecast of 4.44 billion in a Reuters poll of analysts.
Profit was helped by proceeds of 175 million euros from an out-of-court settlement with Liberty Global's German unit Unitymedia over the acquisition of KabelBW.
Europe's largest telecoms operator by revenue said it still expected 2015 EBITDA excluding special items of around 18.3 billion euros at constant exchange rates and free cashflow of around 4.3 billion.
"It has been some time since we have seen positive indications for revenue and earnings in our industry," Chief Executive Tim Hoettges said in a statement. "Our clear strategy with strong investment is paying off."
In Germany, where the market consolidated to three from four players last year, Deutsche Telekom's revenue from mobile services rose 2.8 percent, helped by its fast 4G mobile network and the popularity of the iPhone 6. Deutsche Telekom raised investments by more than a fifth in the quarter to 2.5 billion euros as it upgraded its networks in Europe and the United States, where it owns 66 percent of T-Mobile US.
Last month, T-Mobile US reported first-quarter results that slightly beat expectations after it added 1.8 million customers, taking its total to 56.8 million.
The US business is Deutsche's biggest single market in revenue.
Excluding the effect of the weak euro, adjusted EBITDA rose 5.6 percent, Deutsche Telekom said.
French rival Orange, which depends heavily on its home market, last month reported a 0.9 percent drop in first-quarter sales while restated core profit fell 1.9 percent.