It's more on mobile data these days, granted if you were hammering your connection constantly 24/7 i.e. uploading torrents constantly I could see a ISP getting in touch.
20 days worth:
RX bytes:123398766998 (114.9 GiB) TX bytes:548948956280 (511.2 GiB)
I use Du Meter so that I can see network throughout but it can also log data usage and generate reports.