Hundreds of thousands Canadians got an unexpected letter from their internet service provider this week: a promise to lower their bills starting next year, without any corresponding decrease in their service.

Ontario-based ISP Teksavvy told its customers this week that they can expect lower monthly bills starting in 2017, because of a recent CRTC ruling.

In October, Telecom ruled ruled that incumbent providers were charging third-party ISPs like Teksavvy too much to access the so-called "last mile" of their networks, from the street to home connections. 

An earlier 2010 ruling had mandated that the big companies charge no more than their own costs plus a 10 per cent markup, but the October decision found they were charging far more than that — and ordered them to stop doing so, at least on an interim basis.

"Competitors that provide retail internet services to Canadians using wholesale high-speed services must have access to these services at just and reasonable prices," CRTC chair Jean-Pierre Blais said at the time. "The fact that these large companies did not respect accepted costing principles and methodologies is very disturbing."

Teksavvy echoed that sentiment in its own letter this week, giving the CRTC decision the credit for its corporate decision to lower prices.

"Correcting wholesale network access rates to a fairer level lets us create more savings for our customers, get back to innovating on service and features, and — we hope â€” spur a more competitive telecom market in Canada," Teksavvy said in its letter to customers. "We believe that that's very positive for consumers."

Exactly how much bills will be reduced depends on the area and level of service, but almost all Teksavvy customers have been advised they will be saving some money every month starting in January. Some have also been advised they can expect an upgrade in their download or upload speeds, too, and possibly even an increase to their data caps.

There is a small catch, however. Because the CRTC ruling was only interim, it could theoretically be taken away if the regulator doesn't implement a long-term solution. That is why the company is encouraging its customers to contact the CRTC and let it know they like the new rules.

"We invite you to sign our "#ThanksAgainCRTC" form here, and we will let your government representatives know you're pleased with these changes," Teksavvy said in the letter.

The regulator acknowledged the campaign in a tweet of its own on Tuesday.