* Q3 net loss 87.1 mln riyals vs net loss of 122.1 mln riyals a yr ago
* Q3 revenue 395.6 mln riyals vs 315.8 mln riyals a yr ago
* Subscribers top 1 mln, up 26 pct from a year earlier
* Average revenue per user rises 8.4 pct to 121 riyals
By Matt Smith
DUBAI, Jan 16 (Reuters) - Vodafone Qatar, an affiliate of Vodafone Group, reported a narrowing third-quarter loss on Wednesday as its subscriber base rose by a quarter and revenue per user grew.
Vodafone, which ended Qatar Telecom's (Qtel) domestic monopoly in 2009, made a third-quarter net loss of 87.1 million riyals ($23.92 million) in the three months to Dec. 31, according to Reuters calculations.
That compares with a loss of 122.1 million riyals in the year-earlier period. The operator's financial year starts on April 1.
Quarterly revenue was 395.6 million riyals, up from 315.8 million riyals a year ago.
Vodafone Qatar launched post-paid contract services in June, which the operator hopes will help woo subscribers from Qtel and improve margins. Customers on post-paid contracts are typically wealthier and spend more on telecoms as well as being less likely to switch operators.
Vodafone had 1 million mobile customers as of Dec. 31, up 26 percent from a year earlier.
Third-quarter average revenue per user (ARPU), a key metric for the telecom sector, was 121 riyals, up 8.4 percent year-on-year.
Vodafone, which owns 23 percent of Vodafone Qatar, in November extended a contract to manage its Qatari affiliate until 2018.