Sony has finally unveiled its Xperia Z1 flagship handset. It has a staggering 20.7-megapixel camera, 2.2GHz quad-core Qualcomm Snapdragon 800 processor in its bowels, 2GB of RAM and a 5-inch Full HD screen.

The 4G phone also features Sony's proprietary Triluminos display technology and will be available in black, white and purple colour schemes. In fact, the only things we're still awaiting are details of which networks will be carrying the device, prices and release date. In the case of the latter, we now know...

Release date

Sony Mobile's new president and CEO let slip to Pocket-lint that the Sony Xperia Z1 will be available from 16 September, less than a couple of weeks away. That might explain why some carriers and retailers were in a rush to get their pre-order pages up online as soon as the phone was announced.

Read: Hands-on: Sony Xperia Z1 review

EE

As the Xperia Z1 is a 4G device, one of the first networks to declare its position has been EE - it runs the most established 4G network in the UK. It has opened a pre-order page for the phone and is offering both the 16GB white and black models on its 4G price plans. The cheapest plan is £26 a month on a 24-month contract. However, that only gives you 500MB of data which is hardly worth the 4G speeds you'll be getting, and the phone will cost £239.99 up front on that plan.

EE's recommended plan is £41 a month for 2GB of data and an up-front cost of £29.99 for the phone. You can get the phone for just £9.99 up front, but you'll have to pay for 10GB of data at £46 a month at least. There are 12-month contracts also available, but expect to pay a higher premium.

One more than decent incentive to get in early is that EE is offering a completely free Sony SmartWatch 2 worth £149.99 with every pre-order on its 4G service.

Orange

Orange is also offering the same incentive as its umbrella company EE. You get a free Sony SmartWatch 2 if you pre-order the Xperia Z1 on one of its 3G price plans. The phone will still be 4G-ready too, so you can choose to upgrade later on.

The cheapest price plans on offer start at £10.50 for 100 minutes, unlimited texts and 100MB of data a month for 24-months, but you'll have to pay £319.99 for the phone itself. If you opt to pay £41 a month, however, not only do you get 1GB of internet, but you also get the phone for just £29.99.

T-Mobile

The other EE offshoot, T-Mobile, also offers a free Sony SmartWatch 2 with every pre-order on its 3G price plan, but prices start at the amazingly cheap £7 a month on a 24-month contract. With that you get only 250MB of data, 100 texts and 50 minutes of talk time, and the Z1 will set you back £389.99, but it's an attractive monthly fee.

There are plenty of other price plans too, across 18-month and 24-month contracts, but should you want to pay the least for the phone itself, £9.99 up front, you'll need to pay £62 a month over the full two years. You do get unlimited minutes, texts and data mind.

Phones 4u

The final vendor to have shown its hand so far is Phones 4u. It too is offering an incentive or two for pre-orders. However, with the UK retailer you get a choice between a free Sony SmartWatch 2 or a half-price Sony Xperia Tablet Z with £65 worth of content. Those are available on 3G and 4G pre-orders, while a £120 wireless speaker is added to the bundle for free on 4G plans.

Like the others, it is open for pre-orders for the white and black 16GB Xperia Z1 models. But is also offering Vodafone price plans as well as EE, Orange and T-Mobile's.

Perhaps the most attractive offer is on EE's 4G network with 10GB for £46 a month. That particular plan will give you the two freebies and the Z1 at no up-front cost whatsoever.

Vodafone 

Vodafone has confirmed that it will be stocking the 4G capable Xperia Z1, however that's all the company has said at the moment. There is no pricing or release date as yet, although customers signing up to a 4G contract will get either their Spotify premium subscription or Sky Sports Mobile costs paid for. 

The others

We still haven't heard directly from O2, Three or the Carphone Warehouse. We'll update as more details come in soon.