iPhone 4S
iPhone 4S Apple

The iPhone 4S is going to be, without doubt, one of the most popular Christmas gifts this year; with its improved 8-megapixel camera, super-fast A5 processor and personal assistant Siri, the 4S is one of the best smartphones on the market. But it's not quite that simple. There's a plethora of different networks and tariffs to choose from, so here at the International Business Times UK we've compiled a guide to the best deals available.

If you're stuck in the middle of a contract, or have a great deal that you don't want to change, then buying the iPhone outright is your only option. This means spending a lot of money up front, but then you're free to use any SIM card you like. Also, buying outright then looking for a great deal elsewhere is the cheapest way to have an iPhone in the long term.

The iPhone 4S is priced as follows:

16 GB - £499

32 GB - £599

64 GB - £699

For those who can't quite stomach the SIM-free prices, don't worry. Below we've outlined a few of the best deals around for the iPhone 4S.

Vodafone

£26 per month - 100 minutes, 100 texts, 250mb data. iPhone 4S price; 16GB - £359, 32GB - £439, 64GB - £519

£36 per month - 600 minutes, unlimited texts, 500mb data. iPhone 4S price; 16GB - £159, 32GB - £239, 64GB - £319

The above prices are for 24-month contracts; 18-month contracts cost about £4.50 more per month, and it's an extra £10 per month for a one year contract.

Orange

£20 per month - 50 minutes, 50 texts, 100mb data. iPhone 4S price; 16GB - £309.99, 32GB - £449.99, 64GB - £519.99

£31 per month - 200 minutes, 200 texts, 500mb data. iPhone 4S price; 16GB - £169.99, 32GB - £269.99, 64GB - £379.99

T-Mobile

£25.54 per month - 100 minutes, 100 texts, 500mb data. iPhone 4S price; 16GB - £239.99, 32GB - £379.99, 64GB - £449.99

£35.75 per month - 600 minutes, 500 texts, 500mb data. iPhone 4S price; 16GB - £99.99, 32GB - £219.99, 63GB - £269.99

Three

£30 per month - 300 minutes, 5000 texts, 500mb data. iPhone 4S price: 16GB - £129, 32GB - £219, 64GB - £309

£35 per month - 2000 minutes, 5000 texts, 'all-you-can-eat' data. iPhone 4S price: 16GB - £99

O2

£15.50 per month - 100 minutes, 500 texts. iPhone 4S price: 16GB - £299.99, 32GB - £399.99, 64GB - £519.99

£31 per month - 600 minutes, unlimited texts. iPhone 4S price: 16GB - £99.99, 32GB - £199.99, 64GB - £269.99

O2 doesn't include data in its price plans, and instead offers three data packages as bolt-ons; these are priced at 100mb - £3, 500mb - £6, 1GB - £10.

With Christmas just 20 days away you need to be quick, as we're already hearing reports of delays with shipments of iPhones from some retailers, so to make sure there's an iPhone under the tree on December 25 you should order as soon as possible.