The service will be available with Samsung JD and J7 devices, Dialog said in a statement.
“Dialog is privileged to join hands with Samsung, to be the first to present next-generation technology of end-to-end IP-based voice communications to Sri Lankan customers," Asanga Priyadarshana, Head of Mobile Business for Dialog Axiata said.
"Dialog operates the country’s widest mobile 4G LTE network, and our customers can enjoy superior call quality alongside a host of value-additions that will enhance their communications experience."
In most countries VoLTE has ended per-minute billing, telecom sector analysts say.
In Sri Lanka and elsewhere many mobile users are turning to technologies such as skype and WhatsApp instead of calling traditional numbers, eating into per-minute revenues of mobile companies.
But users are also using more data to watch movies and do other work online.
Dailog's VoLTE service provides for instant call set-up, HD/Near-Stereo voice quality and ability to share audio content including live music over voice calls.
Customers can also make voice or video calls over VoLTE, whilst simultaneously using 4G LTE data. The VoLTE service is available across Dialog’s mobile 4G LTE network in Sri Lanka which spans over 1,000 LTE sites in all 25 Districts.
Dialog said it had previously been the first telco in South Asia to to launch 3G and HSPA+ services, commercial mobile 4G LTE service in 2013.