Canadian telecom company Telus Corp's (T.TO) third-quarter profit missed analysts' estimates as it spent heavily to expand its wireless and fiber-optic networks and add more subscribers in a fiercely competitive industry.

Vancouver-based Telus faces increasing competition from Shaw Communications (SJRb.TO), which has rolled out new internet and television products and is also building up a low-cost wireless business.

Telus said on Thursday its capital expenditure for wireline unit rose 19 per cent in the quarter, mainly as it boosted its fiber-optic network. Total operating expenses rose 3.6 per cent.

Shaw also reported last month an increase in costs that squeezed its margins.

Telus said it added about 115,000 new wireless postpaid customers in the quarter, compared with RBC Capital Markets' expectation of over 99,000. By comparison, Rogers added 129,000 new wireless postpaid subscribers in the latest quarter, while Bell added 117, 182.

The company also said churn rate, or the percentage of subscribers who discontinued services, fell to 0.86 per cent from 0.94 per cent a year earlier.

Average revenue per user (ARPU) for wireless services rose 3 per cent in the quarter.

"Our capital investments have been instrumental in the success of our wireless and wireline growth strategy, which has now delivered 28 consecutive quarters of wireless ARPU growth and 20 successive quarters of wireline EBITDA growth," Chief Executive Darren Entwistle said.

Telus said it expects capital expenditure of about $2.85 billion for 2018, slightly lower than the estimated capital expenditure for 2017 of about $3 billion.

Excluding one-time items, the company reported a profit of 66 cents per share, missing the average analyst estimate of 69 cents per share, according to Thomson Reuters I/B/E/S.

Net income attributable to shareholders rose to $367 million, or 62 cents per share, in the three months ended Sept. 30 from $348 million, or 59 cents per share, a year earlier.

Operating revenue rose 4 per cent to $3.37 billion.

The company also raised its dividend to 50.5 cents from 49.25.

- with files from BNN