The first single-epitaxy top-emitting vertical-cavity surface-emitting laser emitting in the 1.55-1.61 μm wavelength region is reported. CW operation is achieved up to 55°C with an optical power of 0.45 mW obtained at 25°C. Error free transmission by these lasers at 2.5 Gbit/s is obtained over 50 km of singlemode fibre without the need for optical amplification