One of consumers’ main complaints about their broadband provider is that too often the best deals are reserved for new customers, while existing subscribers' custom is taken for granted.

Sky's existing customers, however, benefit from a host of offers aimed specifically at them, especially if they add extra services to their bundle. These span everything from hardware upgrades, such as Sky+ HD boxes, as well as cut-price offers on Sky Talk packages and additional TV channels.

What kind of Sky upgrade deals for existing customers are there?

Sky’s offers for existing customers change from month to month. However, some of the Sky upgrade deals available recently have included:

• 3 months half price when TV customers add Sky Movies to their bundles

• Half-price broadband and calls for Sky TV customers

• A free Sky+ HD box when TV customers upgrade to Sky HD

Why it makes sense to consider Sky upgrades and offers for existing customers

It is a truth universally acknowledged that taking multiple services from a single provider results in lower monthly bills. This is as true for TV, broadband, home phone and mobile as it is for, say, gas, water and electricity.

Taking advantage of Sky upgrade deals also means you’ll have a single bill to pay every month, making it easier to stay on top of your monthly outgoings.

Okay, so that’s Sky upgrades. Why else stick with Sky other than its upgrade deals?

As well as Sky deals for existing customers, Sky also works hard to keep its customers in other ways.

Among these are the option to get two-for-one tickets at 28 attractions around the country on Sundays. Sky also offers free cinema tickets, for films that have yet to go on general release and the option to join the studio audience at the recording of some of its most popular shows. Sky subscribers also get the chance to drink at the Sky Bar at the O2 dome.

Sky’s TV service, which was recognised as the UK’s best at the uSwitch awards 2012, is also among the UK’s best-rated. What’s more, although some carriers offer the chance to add Sky channels to their offering, Sky still retains some of the best as exclusives.

For instance, Sky Atlantic, which picks up perhaps the very best drama and comedy from the US, is not available with any of the TV providers that feature other Sky channels.