T-Mobile’s disruptive uncarrier campaign continued to pay off in the fourth quarter, which saw the nation’s fourth-largest operator add a net 1.65 million customers. T-Mobile posted $6.83 billion in revenues, marking a 40 percent increase over the same period last year, but it also reported a $20 quarterly loss.

The loss can be attributed in part to T-Mo’s aggressive marketing tactics, including paying customers with other service providers up to $350 per line to switch. But as Reuters points out, T-Mobile also plans to raise its capital expenses this year to between $4.3 billion and $4.6 billion, up from $4.2 billion last year. T-Mobile has made big gains over the last year in growing its user base and forcing other carriers to respond to some of its innovative new offerings. But it may have to ease up on the costly marketing efforts to try to try to get its fiscal house in order.