Sky.com/LineRentalOffer
If you’re currently a Sky TV Customer, then you can get 6 months free weekend and evening calls to UK landlines, and Sky Talk Line rental for a little as £5 a month from the date of activation. Once your six months is up it’s then £10 a month.
It’s looks a pretty good offer, however you do need a BT Phone Line and rental for that cost £10.50 a month with paperless billing. Remember though you may already be paying for that with your currently landline!