The Siemens Gigaset SL400A is a top-range and compact DECT phone with answering machine, which delivers the performance you should expect a phone of it’s price to. Offering a wealth of DECT features, excellent sound quality, stylish design, and reliable usability, the SL400A is an excellent premium home phone aimed at discerning users with a penchant for the best that money can buy.

Here’s our full review:

Design & build

The first thing you notice about the SL400A is the way it looks; the chrome-like metal casing and large colour display convey that this is a top-quality product. With a starting price of £94.99 for the single, it is certainly expensive but when it does look and feel like you would expect a phone of this cost to. The genuine metal-frame gives the handset added weight and whilst one of the smallest phones on the market it feels like one of the most solid (and comes with Gigaset’s standard 2 year warranty.

top-quality product

The base and charging cradle aren’t much to write home about, both are a rather plain black plastic; thankfully the main base is separate from the handset, so can be kept discreetly by your phone line. The charging cradle of the SL400A is a sleek black, which does compliment the bezel around the screen, however, I would have preferrered to have seen a solid metal cradle as used with the Gigaset SL910A.SL400a_feature

Ease of use & set-up

As with most Gigaset phones (in fact, most modern home phones) the SL400A is simple and straightforward to set up for use. Included with the phone is a clear and easy to follow Quick Start Guide in addition to a more exhaustive User Manual, which you can use to look up more specific functions and features. The main menu consists of icons and text making it easy to navigate through; there is also an option for larger font, which could prove useful if you’ve forgotten to put on your specs but unlikely to make a difference to anyone with significantly poor eyesight. The buttons on the plush keypad are a reasonable size for such a small handset, and responsive to the touch.


SL400AThe SL400A is packed with features to take advantage of – all the basics are covered: phonebook (impressive memory for up to 500 entries, and the ability to store up to 3 numbers per entry), answering machine (45 minutes recording time), Caller ID, loudspeaker, call lists, and a convenient analogue clock screensaver! There are more – you can check out the full specification here.

In addition, it also boasts a few high-end perks, such as Bluetooth (ideal for hands-free calls if you have an old Bluetooth headset kicking about), and the expansive phonebook memory can be managed conveniently via Gigaset’s QuickSync software, which enables you to transfer contacts from your PC or laptop (via USB or Bluetooth). This can also be used to add images to contacts stored on your phone for Picture Caller ID; or store alternative screensavers to the clock. You can also personalise the SL400A by importing your own ringtones.

And for new parents, grandparents or designated babysitters, there is also a room monitoring feature, which means the SL400A can double up as a baby monitor. You simply keep the handset in the room with your child and if the noise reaches a certain level, that handset will place a call to you. This feature works better when you have more than one handset, as it still means you can receive calls to your landline (the ringer is disabled when the room monitor function is activated); however, you can program the handset to call your mobile so it does work if you only have the single version.

Sound quality

The sound quality on the SL400A is what you would expect of a phone of this calibre – put simply, excellent. Whether using the earpiece or loudspeaker, the call clarity is impressive and the volume is easily adjustable during conversations. The recipient of our test calls reported no problems hearing us.

Range & battery life

When we tested the SL400A for range we were able to get over 45 metres from the base before the call started to break up, and we were similarly impressed with the outdoor range as well. As with all Gigaset cordless phones, the SL400A is repeater compatible so it’s possible extend the range if required.
The handset takes a 1000 mAh Li-Ion battery, which can make finding a replacement problematic (though there are usually a few sellers on Amazon with stock). On a full charge we were able to use the handset provided over 14 hours continuous use, and lasted well over a week in standby mode.


If you are looking for the crème de la crème of home cordless telephony, the Gigaset SL400A is definitely a contender. It may not boast a Touchscreen or Android like other premium models but it delivers excellent call quality, good range, and certainly looks and feels the part. One of our top choices for 2014, the SL400A is a phone destined to impress.