Carphone Warehouse has posted a rise in sales and profits as the mobile phone specialist increased its market share.

The retailer posted an 8.3% surge in first-half like-for-like sales in the 26 weeks to September 28.

Group headline pre-tax profits rose to £19m from £4m last year. However, the retailer fell to a statutory pre-tax loss of £25m, from a profit of £8m last year, because of exceptional costs of £31m as it exits France and acquisition-related costs of £13m.

Sales growth in the second quarter slowed to 3.6% from 13.2% in the first quarter, primarily because of tougher comparatives.

The retailer said the slower second quarter was also due to networks putting less emphasis on investing in upgrades and new subscriptions in preparation for the wider roll-out of 4G.

Carphone Warehouse reported an “encouraging performance” in Spain and “continued progress towards profitability” in Germany.

Carphone Warehouse chief executive Andrew Harrison said: “Carphone Warehouse has delivered good like-for-like growth for the half and for the fifth successive quarter.

“This is a strong performance given the reduced marketplace activity ahead of the wider launch of 4G across Europe and the continued double-digit decline of the prepay market. We have increased market share and grown EBIT year on year.”

He added: “Looking ahead, we reiterate our full-year guidance. We are in excellent operational shape to take advantage of the key Christmas trading period and are encouraged by the growth of 4G as it starts to arrive across all the major networks.”