King Koil Mattress Review – Should You Buy?

lauren hall 1
written by sleep expert Lauren Hall

King Koil Mattress Review

King Koil mattresses are American-made products that are manufactured with input from the International Chiropractors Association in order to produce mattresses that promote proper spinal alignment meaning King Koil has some of the best mattresses out there when it comes to sleeping comfortably and combatting back pain.

They are known for having above-average temperature regulation features and a build that reduces movement across the bed.

The brand has released a wide variety of them in all sorts of makes and builds. The question is, which one is right for you? We’ve put together a list of King Koil mattresses and their defining features to help you decide.

In our King Koil mattress review, this collection mainly houses hybrid ones. All of them are infused with temperature regulation technology in the form of King Koil’s AvantaGel and iFusion designs.

They are also fitted individually with 1000+ Perfect Contour Reaction Coil Systems which provide added comfort. All mattresses in this collection have silk and wool blend covers that are infused with cooling gel foam for temperature regulation.

Kingsley Line

The King Koil Kingsley mattress line features hybrid mattresses with more focus on innerspring design. These are the mattresses in the line:

  1. Kingsley Firm – a medium-firm.
  2. Kingsley Plush – a medium soft.
  3. Kingsley Euro Top – a very soft.
Each mattress features a support base fashioned from pocketed coils that are carefully encased in foam followed by a base layer made from polyfoam.

The comfort layers on the Kingsley Firm and Kingsley Plush mattresses are built with one layer of memory foam followed by a polyfoam layer while the Kingsley Euro Top mattress has two layers of polyfoam beneath its comfort memory foam.

  • This one line is easily the most comfortable that King Koil has to offer.
  • The price range of the Kingsley line is much higher than other similar mattresses from other brands.

Montego Line

The Montego Line features hybrid mattresses fitted with Energex rapid response foam that provide extra comfort and conforming contours to the memory foam layers. These are the ones in the line:

  1. Montego Luxury Firm – a medium-firm mattress. This one has memory foam, gel memory foam, and polyfoam layers on top and therefore feels almost like a memory foam mattress out of the three in the line.
  2. Montego Luxury Plush – a medium soft mattress. This one comfort layer is simply fitted with memory foam.
  3. Montego Luxury Pillow Top – a very soft mattress. This one has a comfort layer system that features gel memory foam and polyfoam layers, between which are extra memory foam inserts.

Each mattress has a constructed support core layer that features foam-encased pocketed coils.

  • These mattresses are extremely comfortable and have plenty of cushioning.
  • The price range of the Montego line is much higher than other similar mattresses from other brands.


The World Edition Collection

The World Edition Collection line exclusively showcases innerspring mattresses that are fitted with a body-conforming encased coil technology known as the 789 Contour Flex EC with K2 Edge.

This technology allows the mattresses to contour and respond to your body’s curves and edges and reduces movement across it. Each coil is steel reinforced and incased to relieve pressure and provide edge-to-edge consistency when sleeping.

Everything in this line comes with quilted covers infused with AvantaGel gel foam for temperature regulation and added durability. And as ever, the King Koil standard remains throughout.

Siena Line

The Siena Line only features one mattress: the Siena Firm mattress, which is one with high firmness. Its topmost layer is made from polyfoam for comfort, and its support center is constructed with pocketed coils over a polyfoam base layer, which reinforces the coils’ strength.

  • This mattress is inexpensive and offers decent value for money.
  • The mattress doesn’t have that many pressure relieving properties, especially compared to similar mattresses from other brands that share its price.


Sydney Line

Although it is from an innerspring mattress collection, one of the Sidney line mattresses may be classified as hybrids by some.

  1. Sydney Firm – a medium-firm mattress. This one has a top comfort layer made from polyfoam and a second layer beneath it made of more foam for added comfort.
  2. Sydney Euro Top – a medium soft mattress. This one has a top comfort layer made from memory foam and a second layer beneath it made of polyfoam for added comfort.

Both mattresses in this line have a support center constructed with pocketed coils over a polyfoam base layer, which reinforces the coils’ strength.

  • The layers in this line focus a lot on cooling properties, making it a great bed for temperature regulation.
  • The foam lacks in thickness, meaning it may not offer sufficient support to some sleepers.


Monaco Line

The Monaco line doubles up on features with its iFusion Lumbar Support foam that helps with spine alignment and to relieve pressure in the back and neck.

  1. Monaco Plush – a very soft one.
  2. Monaco Euro Top – a medium soft one.

Both mattresses come with an AvantaGel top foam layer and a base layer of the usual King Koil coil system, with the lumbar support foam slotted in between them.

  • The mattresses in this line offer a good amount of back support and have great thermal regulation. On top of that, they’re more inexpensive and decently affordable given what they have to offer.
  • There may be less pressure point relief in this mattress as it lacks comfort layers.

The World Extended Life Collection

There is only one line in this collection, which is focused on innerspring/hybrid mattresses that make use of Talalay latex foam.

Athens Line

Both in this line make use of Talalay latex, a kind of material that is more responsive than memory foam and also often more expensive.

Both also make use of superior, high quality, and high-density foams as well, which offer added strength and durability. The spring systems in both mattresses make use of the 1000+ Perfect Contour Reaction Coil System. The mattresses in this line are:
  1. Athens Firm – a high firmness mattress. This one has its layer of Talalay latex sandwiched between two high-density polyfoam layers. Its fabric cover is also stuffed with a similar foam. Meanwhile, its support core is made of the same foam encased pocketed coil as other models.
  2. Athens Plush – a medium-firm mattress. This one has a top layer of high-density polyfoam, which sits atop iNergex rapid response memory foam. Beneath that is the Talalay latex layer, and the support layer is constructed from pocketed foam encased coils. The mattress comes with a fabric cover that is gel-infused.

This is likely to be a very comfortable mattress line. The Talalay latex adds a bounce and responsiveness to the mattress that other models do not have.


The mattress may sleep hot for some individuals. In addition, it is quite expensive when compared to other mattresses from other brands that use similar materials.

The World Luxury Intimate Collection

This collection currently only has one mattress line of innerspring/hybrid type mattresses. It is easily the most luxurious of the mattresses that the brand offers.

Vienna Line

The Vienna line is an interesting part of the King Koil brand as it features the topmost layer made from Jomo wool as one of its integral characteristics.

All products in this line also make use of the AdvantaGel temperature regulation gel memory foam beneath the Jomo wool layer. These are the mattresses in the line:

  1. Vienna Plush – a medium soft one. Under the top comfort Jomo wool and gel memory foam layers, the mattress features GelResponse Latex and iNergex rapid response memory foam.
  2. Vienna Firm – a medium-firm one. Under the top comfort Jomo wool and gel memory foam layers, the mattress features GelResponse Latex and iNergex rapid response memory foam.
  3. Vienna Euro Top – a medium soft mattress. Under the top comfort Jomo wool and gel memory foam layers, the mattress is fitted with ThermoGraph temperature regulation foam, GelResponse Latex, and iNergex rapid response memory foam. It also has an added layer of coils above its support core in the form of micro coils.

The mattresses also come with the usual 1000+ Perfect Contour Reaction Coil System, meaning all of them to have support cores fitted with foam encased coils.

  • These mattresses provide luxury and comfort thanks to their many layers and superior materials.
  • This line is the most expensive that King Koil has to offer.


The iMattress Collection

This collection features King Koil’s mattress-in-a-box designs. They are all fitted with covers that are infused with copper yarn in order to promote healthier skin and remove odors.

All the mattresses in this line are relatively good quality and reliable, but they all share one negative side: they are often more expensive than other similar ones from competitor brands. These are the mattresses in the collection.

  1. G10 Firm – This medium-firm mattress is fitted with a top layer of TriFusionFOM for temperature regulation, followed by rapid response iNergex memory foam and a high-density polyfoam support base that conforms to the body and adds to the mattress’ durability.
  2. G12 Plush – This medium-soft one has the same features as the G10.
  3. Hybrid Firm – This medium-firm mattress has a top comfort layer of iNergex rapid response memory foam and high-density polyfoam. Like mattresses in the World Edition Collection, the Hybrid Firm has the 789 Contour Flex encased coil system with K2 Edge as its base support.
  4. Hybrid Plush – This medium-soft one has a top layer of TriFusionFOM for temperature regulation, followed by rapid response iNergex memory foam. It has the same coil support base as the Hybrid Firm.
  5. XS 10 Hybrid Firm – This medium-firm mattress is one of the more luxurious in this line. Beneath its copper-infused cover, it houses iFusion technology foam that regulates the mattress’s temperature, and its support base is a 630 Contour Luxury Plus Encased Coil System.
  6. XS 50 Hybrid Plush – This medium-soft one has the same features as the XS 10.


About King Koil Mattresses

In 1898, Samuel Bronstein realized his dream: he founded United States Bedding in St. Paul, Minnesota. What started out as six employees in a small factory has steadily grown.

Throughout the early 1900s, US Bedding added employees, expanded manufacturing, and became innovators in the industry. During the 1930s, US Bedding greatly improved the bedspring and was looking for a new name for its product.

The King Koil name was born and now, today, King Koil mattresses can be found in more than 90 countries throughout the world. The King Koil Mattress Company has Hand Crafted mattresses since 1898 and today manufactures products all over the world.



The various King Koil brands and models are guaranteed against manufacturing defects in workmanship and/or materials. However, it’s worth checking warranty details specific to each sleep system you purchase. 

King Koil pride themselves in their customer service so if there is a problem you’ll have their full support.

If you observe a defect, just contact the retail store from which you purchased your sleep set. If the retail store has closed or you have moved to another location, then contact King Koil customer support.


Smartlife – King Koil has developed a sleep system that adjusts to your unique body size and continuously adapts to the way you move. Smartlife features patented body sensing technology that adjusts to your body while you sleep, giving you support and comfort where you need it. Smartlife’s Smart Cell Technology includes over 80 individual Smart Cells in eight independently controlled zones using thousands of algorithms to give your unique body the support and comfort it needs.

Intimate – The Intimate mattress collection from King Koil is exactly that. A comfort so sophisticated, it transforms our relationship with tomorrow by offering a well-rested tonight. In this contemporary redesign of the Intimate collection. Hand craftsmanship, tailored looks, and exotic materials of the highest quality come together to form a wonderful experience.

Xtended Life Strategically positioned layers of pressure-relieving and cooling comfort foams rest on a durable and zoned encased steel coil system. Together, they harmoniously combine the best of their properties to provide you a consistent sleeping experience year after year.

iBed – King Koil’s latest innovation in luxurious sleep combines enhanced cooling comfort technologies with over 1000 responsive and pressure relieving pocketed coils for ideal support. The iBed collection is conveniently packaged to deliver right to your front door and available in firm, medium, and plush comfort designs.

Luxury The Luxury mattress collection utilizes advanced coil technologies to promote better posture alignment while specialty foams regulate temperature and dispel motion for a deeper night’s rest for all.

iMattress – Cooling comfort, pressure-reducing support, peaceful sleep. Everything your body craves for a comfortable night’s sleep all packaged conveniently in the redesigned iMattress collection. Use this and experience intense comfort all night long. All iMattress beds are available through King Koil’s Express Comfort delivery program, where they are delivered directly to your door

Intimate LS – Delivering handcrafted comfort and unparalleled support, this collection features a rare combination of the finest natural materials and handcrafted details the world has to offer. Crafted without compromise, each time-resilient layer rests over 1000 hand-assembled cotton calico wrapped steel coils, and each mattress is finished with button tufting to ensure years of consistent rest and rejuvenation that will be felt in every last luxurious detail. Temperature regulating foams are innovated with carbon fibers and graphite latex to provide superior breathability and durability while layers of responsibly sourced horsehair, Joma wool, and cashmere create layers of comfort for optimal sleeping conditions.


A King Koil mattress is not something you want to miss out on. They provide a wide array of the best mattresses you’ll find on the market. 

We hope that now you have this information under your belt you can confidently check out King Koil and find a mattress that’s going to help you get the best night’s sleep you’ve ever had.

Related Post: Best Memory Foam Mattress [Review]