Firstly, find a friend to help you – mattresses can be heavy!

All our beds are wrapped in heavy duty plastic which can be recycled. Mattresses are packed flat:

  • Place the mattress on the bed where it will be located
  • Remove the plastic wrapper


We know you will be itching to get into bed, but the first thing we advise you to do is retain your receipt and guarantee booklet safely. You will need these in the event you need to report a complaint under your Guarantee.

Don’t you love the smell of new things? All mattresses are manufactured at the time of order and sealed in protective wraparounds to ensure perfect presentation upon arrival. Smells are good news as it means your mattress has been made freshly for you! Initial odours are common after removal of the protective packaging and are normal. Most people don’t even notice, but those with heightened senses may report a “foam” our, or a damp or musty smell. On taking delivery, it is a good idea to leave the mattress to air in a well-ventilated room. Regularly airing your mattress ensures proper maintenance and will help dissipate any odours.

Others are more sensitive to smells than others. Whilst a mattress may always retain an inherent odour if you smell it at close quarters, you should notice that any smell which is noticeable when you enter a room has greatly reduced within 3 months, providing you have followed the instructions above.

It’s a good sign if the surface of your mattress feels damp when it is unpacked – it means your mattress conforms to all UK Fire Regulations. We are required to treat certain mattress fabrics with a harmless Fire Retardant at source, in order to comply with the Regulations. This material is salt based, which will absorb moisture. When weather conditions are humid, or there is a lot of rain, this effect will be exaggerated, and when the mattress is packed into a bag, condensation may form, causing a damp feeling on the mattress. The feeling of damp will disappear quickly and should not materialise again, unless your mattress is kept in a particularly humid room.

Body impressions are a characteristic of quality mattresses working as they should by conforming to the shape of your body. You should expect to see impressions, sometimes described as settlement or “dipping”.

With regards to settlement, what is acceptable can vary from case to case depending on the individual using the product, the depth of the mattress, and the materials used. The Furniture Industry Research Association (FIRA) provide guidelines which suggest that settlement of between 2 and 4cm in depth is acceptable for a mattress that is 5 years old. In addition, settlement depth may be higher when the mattress has been recently used, and if not used for a while, the mattress will recover some height. We will not normally consider settlement to be a fault. In the event of a dispute in this area, we are able to arrange for a FIRA Inspection at a cost of £50 + VAT. In the event a fault is found within the Guarantee Period, the £50 + VAT will be refunded and the product replaced or repaired.

Natural fillings will be subject to a greater degree of settlement, and may result in patches of uneven wear and tear – again this is normal. You can make sure settlement is even by rotating the mattress as above.

No! Your mattress and bed are designed to be lain on, not sat on for long periods of time. If you do, you will notice uneven wear in the mattress Please don’t let the children (or adults for that matter!) jump up and down on the mattress!

Like a new pair of shoes, your mattress will soften after a period of time, particularly in the areas you lie (sometimes described as “dipping”). This is not a problem, and is actually a sign the mattress is working with the weight of your body. There is even a British Standard on this (BS3379:2005)

If a mattress has been displayed in a shop as a “floor model” that mattress may have already been bounced on many times, and may feel softer than the new mattress you will be delivered. It can
take a few weeks, even months, for the mattress to fully settle down.

We recommend the use of a mattress protector in addition to the removable washable covers. Unfortunately, if a mattress is soiled in any way due to dropping a glass of wine for example, your Warranty will be invalid, and a mattress protector helps prevent this.

Where your mattress features a removable, washable cover or integrated mattress protector, you are able to machine wash at 40 degrees. When you remove the cover/mattress protector, please remember that the product has been used, and therefore you may see signs of wear and tear that you would not otherwise see with a fixed cover product. You may see some slight damage to the sleeping surface, small indentations, discolouration or even small tears. All of these are considered normal wear and tear, and do not constitute a manufacturer’s fault.

If the label does not state “removable, washable cover” then you should not remove the cover under any circumstances. We occasionally use “zipped” covers that are not designed to be removed. Where the cover is not intended to be removed, the zip will be locked using a “cable tie” device. Please note that if you then remove the cover, your warranty will be void.

All of our products comply with the appropriate legislation as detailed in The Furniture and Furnishings (Fire) (Safety) Regulations 1988. Certificates are available on request.

All of our products are manufactured in the UK. Find out more here on our About page.

We recommend you use your mattress with a new base supplied by us, for a longer life, and better mattress performance. Placing a new mattress on an old base may contribute to a fault developing within the mattress. When the mattress is being used on a slatted bedframe, we ideally recommend that the space between the slats is not more than 7.5cm to minimise uneven softening and settlement and that there is a central support leg for double sizes and above.

We manufacture our mattresses to metric sizes as below (for standard sizes):

  • Single 90cm x 190cm (3ft x 6ft3)
  • Double 135cm x 190cm (4ft6 x 6ft3)
  • King 150cm x 200cm (5ft x 6ft6)
  • Superking 180cm x 200cm (6ft x 6ft6)

In line with BS 1334:1996, we have a +/- 20mm size tolerance on all mattresses and beds. In addition, many bed frames are still manufactured using imperial measurements (which are in brackets above). These imperial measurements are larger than the metric equivalent (so a “double imperial” frame would be 137cm x 191cm). If you have purchased an imperial frame with a metric mattress, the frame is likely to be bigger and therefore there may be a small gap. We believe that once bed linen is in place, this will be more that suitable.

If you feel your product develops a fault within your guarantee period please follow the below process. However, please read this document to make sure what you believe is an issue, is not actually normal
before raising a concern.

Please also note that the Warranty does not cover:

• A normal increase in softness in the polymer filling material or a decrease in the slow recovery
performance, which does not affect the pressure relieving properties.
• Any smells relating to the mattress
• Body indentations relating to normal settlement
• Level of perceived comfort
• Where a product has been purchased online, and the complaint is due to the “feel” of the mattress
• Where the mattress has had more than 1 owner

The warranty will cease to apply if GNG Group Ltd finds that during the warranty period, any of the following applies:
• Abuse, misuse, or general wear and tear
• The mattress has been used on a slatted base with slats more than 7.5cm apart
• Any causes other than faulty manufacture or materials
• Where the product is soiled, has become wet, or in an unsanitary condition
• Where the customer care hints detailed in this document have not been applied – this includes not rotating the mattress as recommended
• Where the cover has been removed where the label does not state “removable, washable cover:
• A new mattress has been used with an existing, damaged divan or a divan that is deemed to be of unsuitable quality

In order to register your concern you will need to report the problem in writing to the retailer from whom you purchased the bed and they will handle your warranty claim on your behalf and liaise with us.

You will need to provide proof of purchase in order for them to investigate any issue under your warranty.

Should your retailer no longer be in business, or you feel that they are not assisting you, then please contact our customer service team on and have the following available – proof of purchase, including date of purchase, product name and size plus description of problem. Our experienced team will give you an opinion on your issue .If your issue is covered by the FAQs, but you wish for us to arrange an inspection via a Third Party, we are able to instruct the Service Team of the Furniture Industry Research Association (FIRA) who are completely independent and linked to the Furniture Ombudsman. We will ask you to pay £50 for this service by Credit Card – in the event that FIRA deem the mattress to be faulty, we will repair or replace the mattress in line with the below on a like-for-like basis (or for an equivalent specification in the event your product is discontinued) and refund your £50.

10 year warranty (5 years guarantee + 5 year warranty).

If there is a manufacturing fault with the mattress within the first 5 years after date of purchase we will replace the mattress free of charge with the same specification as the original purchased product (or the closest equivalent in specification product if the original mattress is no longer available). If a manufacturing fault is found after 5 years of date of purchase; the 5 year warranty will be valid;

Year 6 Pay 20%
Year 7 Pay 40%
Year 8 Pay 60%
Year 9-10 Pay 80%

The percentage contribution is towards a new mattress of the same specification as the original purchased product (or the closest equivalent in specification product if the original mattress is no longer available).

The percentage is calculated against the RRP price of the product being supplied under the warranty.

This price will be calculated against the product being supplied relevant to the price at the date of the warranty claim being processed.


Find Your Best Sleep

Everyone sleeps differently and has their own idea of what comfort means for them.
And some have particular needs too, At Sonlevo we truly have it all covered.

Sonlevo Mattress Gold
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The first product in the UK to feature revolutionary TRUE GEL technology. The GEL grid is 80% air so gives responsive, breathable support, with no pressure, and is never too hot, never too cold.