Objective - The telecommunications industry in Southeast Asia continues to grow, as evidenced by the market penetration that continues to increase from 3.8% in 2000 to 71.1% in 2017. However, although the number of subscribers and revenue from telecommunication operators continued to grow between 2008 to 2017, the data shows that the EBITDA margin and ARPU value decrease with the growth rate (CAGR) -1.12% and -4.42%.

Methodology/Technique - This study measures and analyzes the efficiency of 14 operators in Southeast Asia between 2008 to 2017 by using the Data Envelopment Analysis (DEA) method.

Findings - The results show that of the 14 telecom operators examined, Telkomsel (Indonesia) was the most efficient operator with an efficiency value of 0.97 and contributed from subscriber and revenue output variables which far exceeded the average of other operators. The most efficient telecommunication companies thereafter were StarHub (Singapore) and SingTel (Singapore) with an efficiency rating of 0.96 and 0.95 as represented from ARPU output variables that far exceeded the average of other operators.

Novelty - True Move operators became the telecommunication companies with the lowest efficiency because the value of its output variables (subscribers, revenue and ARPU) was far below average and did not show any positive correlation to its efficiency value.

Type of Paper - Empirical.

Keywords: Data Envelopment Analysis (DEA); Efficiency; Telecommunication Industry; Southeast Asia.

JEL Classification: M1, M10, M19.