New Delhi, Nov. 5: Those addicted to heavy mobile texting may now have to pay more.

Telecom regulator Trai today issued a directive that allows customers to send only 100 text messages a day at concessional rates from a single mobile number. The directive is aimed to curb pesky marketing texts that continue to defy Trai’s do-not-call guidelines.

There is no upper limit for the number of texts that can be sent in a day, but consumers will be charged not less than 50 paise per text once the number crosses 100 on any particular day.

Service providers are to implement the new regime within the next 15 days. Mobile operators now sell SMS tariff packs that allow customers to send 500 or more messages at 10 paise or less per text.

“Ordinary mobile users will not be affected by this measure. An internal study has shown that on an average, a mobile user sends about 47 text messages a month, and not more than two a day,” a Trai official said.

“To prevent unregistered telemarketers from misusing (concessional) packs or tariff plans for sending bulk promotional SMS, a price restraint has been placed on sending of more than 100 messages a day per SIM at a concessional rate,” N. Parameswaran, principal adviser to Trai, said.

Trai has issued another directive to restrict unregistered telemarketers from sending bulk promotional texts using computers. It has asked operators to put a mechanism in place within three months to ensure that not more than 200 commercial texts are sent containing the same or similar characters or strings or variants from any one source or number in an hour.

Mobile users sending identical non-commercial texts — for instance, “Happy Diwali” — to multiple recipients will not be affected.

Trai is also simplifying the procedure for lodging complaints against unsolicited marketing texts. From tomorrow, complaints can be registered through texts by forwarding the spam text message to 1909 after appending the sender’s phone number and date of receipt of the text.

Mobile operators have been asked to set up a web-based complaint registering system and a dedicated email address to receive such complaints on spam messages and calls.