“Unexpected changes in our billing have forced us into a difficult situation with our Canadian SMS service,” the Twitter blog explains. “We can’t afford to support this service given our current arrangement with our providers (where costs have been doubling for the past several months).”

Twitter will continue to allow Canadian users to update their own accounts over the 21212 shortcode and promises it is working on a “realistic, scalable” solution for the country.

The decision follows a similar move in the UK back in August. Twitter pulled all outbound SMS services from Britain and other nations on the same network then. It took less than a week for a handful of low-cost third-party providers to pop up, trying to fill the void.

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