Twitter has sealed a deal with Bharti Airtel, India’s largest mobile carrier, that will let its wireless subscribers receive tweets by SMS for free, and send them at standard rates. Co-founder Biz Stone said the company had worked “quickly” to get cheap, full-service SMS set up for users in India, because the adoption rates in the region had been “unusually strong.”

This is similar to deals the company brokered with U.K.-based mobile carriers like O2 and Vodafone this summer, to help keep SMS tweets flowing at rates that were bearable for both itself, and U.K. users. (Without deals in place, the company said carriers’ fees were costing it up to $1,000 per user each year to maintain SMS service).

Bharti subscribers can thank Kevin Thau, the company’s director of mobile business development for the deal. Thau was instrumental in getting SMS service restored for U.K. users; at our econSM conference, he even said Twitter was trying to broker SMS and data rev-sharing deals with various carriers.

The deal also speaks to Twitter’s larger goal of continuing to attract more users overall—particularly as growth in traffic to its homepage seems to be flatlining (per TechCrunch). As Stone notes in the blog post: “There are over one billion people with internet access on the planet, but there are more than four billion people with mobile phones and Twitter can work on all of them because even the simplest of these devices feature SMS.”

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