When is a terrabyte of usage on a single consumer Internet access account a problem? When a consumer user is part of the “one percent.” That is one percent in terms of data consumption on a Comcast network in a month’s time.
Roughly, that corresponds (Comcast’s estimates) to a household consuming about 21.7 hours of high-definition format video entertainment every day of the month, based on a terabyte supporting between 600 and 700 hours of HD video, and using 650 as the median case.
Netflix estimates an hour of its HD video consumes about 3 GB per hour, though. In 2014, according to Sandvine, a cord cutter household consumed about 212 GB a month (video and all other uses).
As a rule of thumb, a typical household using Netflix and streaming video should not experience any data consumption limit issues if a 500-gbyte cap is in place, according to WhistleOut.