Frequesntly asked questions

Thinking about buying

Where are your mattresses made?

All of our products are manufactured in the UK, and 100% of our raw materials are sourced through UK based organisations

What is Medical Grade™ foam?

Mammoth’s own innovation derived from healthcare, highly supportive and scientifically shown to improve sleep.
This comfort technology is renowned for its pressure relieving qualities and amazing feel. Not too hard, not too soft, just right.

What are your standard mattress sizes?

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 than suitable.

How will my new mattress be packed, and how do I unwrap it?

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 in 2 way:


Packed flat:

• Place the mattress on the bed where it will be located

• Remove the plastic wrapper


Vacuum Packed and rolled:

• Carefully pierce the outer wrapping of the mattress, and gently pull the plastic away from the mattress

• Place the mattress on the bed where it will be located. The bottom of the mattress is easily discernable from the top of the mattress, so make sure it is the correct way up

• Remove the bag from the mattress

• Your mattress will take a few hours (maximum 24) to fully recover

Do your mattresses come with a warranty?

We provide a standard 1 Year Guarantee on all our mattresses, which protects you against Manufacturing Defects. If you then register your product online, we will extend this to a FREE 10 Year warranty.

Our warranty is based on a 5+5 year warranty. This means that Mattress replaced free of charge if the fault is reported within 5 Years of your purchase. After that, a pro rata amount of your original purchase price will apply as follows

Year 6 20% of the purchase price

Year 7 40% of the purchase price

Year 8 60% of the purchase price

Year 9 – 10 80% of the purchase price

The warranty covers any deterioration, which causes the mattress to have a permanent indentation of considerably more than the guidelines issued by FIRA.

Do Mammoth mattresses comply with UK fire regulations?

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.

Can I use a slatted/divan bed base?

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 bed frame, 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.

After unpacking, what should I do?

We know you will be itching to get into bed, but the first thing you should do is register your guarantee at here.
Please also ensure you keep your receipt or Proof of Purchase somewhere safe.
You will need this in the event you need to contact us regarding your Warranty.

Caring for your Mammoth

Why does my mattress have a ‘new car’ smell?

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 is normal. Most people don’t even notice, but those with heightened senses may report a “foam” odour, 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.

Why does my mattress feel slightly damp?

This is a good sign – it means your mattress conforms to all UK Fire Regulations. You may notice that the surface of your mattress feels damp when it is unpacked. We are required to treat certain mattress fabrics with a harmless Fire Retardant at the 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.

Why does my mattress feel firmer/softer than when I purchased it?

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.

Do I need to flip my mattress?

Fortunately not! You should never “flip” your mattress, but you need to rotate the mattress regularly to encourage even wear. You should rotate your mattress head to foot (180 degrees) every 3 Months.

Can I use an electric blanket with the mattress?

Yes, an electrical blanket is safe to use with any Mammoth mattress and will not affect its performance.

Can I use a mattress protector on my Mammoth?

The use of a mattress protector in addition to the removable washable protector is perfectly fine and will not affect the performance of the mattress.

Are ‘body impressions’ in my mattress normal?

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. Mammoth will consider FIRA’s findings as final. In the event a fault is found within the Guarantee Period, the £50 + VAT will be refunded and the product replaced or repaired.

Customer Enquiries

If you have a question about a Mammoth mattress that you have purchased, you will need to contact your retailer in the first instance.

General Enquiries

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