You don't have to have a landline (for example, VM do broadband-only services) but, the way VM price their packages, the savings minus the landline are often minimal or including the landline may even be cheaper than packages without it. Achieving savings in the long run, however, involves playing the renegotiation game every 18 months to renew at a competitive price.
If you only want broadband, you could probably find much more competitive pricing as a new customer with another supplier, assuming they can offer you an acceptable speed.
