Australia is home to some of the best king-size mattresses in the world. Shoppers have many options at their disposal, but which one is the best?
I've done all the hard work and selected two king mattresses based on customer satisfaction, price, and features.
So whether one is looking for a traditional bed, a memory foam option, or something in between, I have it covered. Let's get started!
A Quick Preview
 | Best Overall – Editor’s Choice Ergoflex 5G Memory Foam Mattress | Read more about this mattress |
 | Best Latex King Size Mattress Peacelily Mattress | Read more about this mattress |
 | Best for Restless Couples Koala Mattress | Read more about this mattress |
 | Best Modern Memory Foam Option Emma Comfort Mattress | Read more about this mattress |
The Best King-Size Mattresses in Australia (November 2023)
Best Overall – Editor’s Choice — Ergoflex 5G Memory Foam Mattress
Highlights
- An all-foam design, great for back pain sufferers and other orthopaedic issues;
- Medium-firm feel, suitable for most sleepers;
- A natural, removable Tencel cover ensures easy maintainers and optimal sleep health.
The Ergoflex 5G is my editor’s choice for the best king-size mattress in Australia, thanks to its excellent pressure relief, eco-friendly cover, and cool temperature regulation. This luxury mattress’s mix of visco-elastic memory foam and a high-density base contours to the body, redistributes weight, and eases pressure points. From my tests, this model had a sinkage of 2.19 inches, and I was most comfortable with the contouring foam cradling my back, lumbar, and spine. The Ergoflex 5G has a similar firmness as the Emma Comfort, with just a difference of 0.01 inches. That means both mattresses serve to cradle and contour to your body in a similar, pressure-relieving manner.
Those who love their mattress natural and free of synthetic materials will appreciate that the mattress cover is 100% natural Tencel - a sustainable and eco-friendly fabric. Also, this cozy cover ensures adequate temperature regulation and comfortable night rest. The result is like having a mattress that lets one sleep on a cloud! From my review, I recorded a temperature of 31.9 degrees Celsius with the Ergoflex 5G. Thanks to its Tencel cover, I felt temperature neutral during my tests and never had issues with night sweats or heat build-ups. The Ergoflex 5G is 0.2 degrees hotter than the Emma Comfort, which means both offer similar cooling qualities for temperature-neutral sleep.
Its beautiful aesthetics featuring grey and white tones immediately adds a sense of luxury to any sleeping environment.
Top athletes understand the ergonomic benefits of memory foam. Hence they find the Ergoflex 5G Memory Foam mattress the right fit for enhancing injury prevention and recovery.
Based on Our Review
While testing the Ergoflex 5G mattress, I experienced support targeted at correcting and aligning the spine in the right frame. This support helped me wake up refreshed as the uncomfortable tension in my body dissipated during the night.
Pros:
- High-quality materials for comfort and durability;
- Luxury aesthetics adds luxury to any sleep environment;
- Minimal motion transfer, great for couples.
Cons:
- Some customers find the mattress too firm;
- Not that great for people who sleep strictly on their sides.
Best Latex King Size Mattress — Peacelily Mattress
Highlights
- The perforated latex layers don’t retain heat, helping you stay cooler at night;
- The uniform springiness of the latex layers redistributes your weight, effectively relieving pressure;
- Made of all-natural materials to ensure your sleeping space is non-toxic and safe for children.
The Peacelily is my best latex king-size mattress due to its excellent cooling qualities, buoyancy for ease of movement, and pressure relief. Typically, if you’re looking for a king-size mattress, you’ll share it with a partner or co-sleeping. Sharing a bed can quickly lead to heat build-up, which can cause night sweats and frequent wake-ups with the wrong mattress. Luckily, the Peacelily’s latex doesn’t hold on to heat like memory foam is known for. From my review, I recorded a temperature of 30.3 degrees Celsius, which was low enough to keep my temperature cool, and I was free of night sweats. This is 1.3 degrees cooler than the Koala, which means the Peacelily is a better choice for hot sleepers needing a cool solution.
Latex is well-known for its springy qualities, which the Peacelily showcases remarkably well. While testing this model, I instantly noticed the natural bounce of the latex layers, keeping me buoyant and free to switch sleeping positions with minimal effort. I measured the Peacelily to have a bounce of 9.76 inches. This was 2.36 inches bouncier than the Koala, making the Peacelily the better option for sleepers needing a responsive, buoyant feel to their king-size bed.
Another feature sleepers who want the best king-size mattresses may like is the Peacelily’s ability to relieve pressure. Latex can easily disperse body weight over a large area. From my tests, I measured sinkages of 2.01 inches and 1.87 inches on the medium and firm sides, respectively. I felt well-cushioned on both sides, with enough cradling around my limbs while supporting my spine. It didn’t conform as closely as memory foam typically does, but the relief I felt was measurable, and my muscles were tension-free. The Peacelily’s medium side has 0.04 inches less sinkage than the Koala on its medium-firm side. That makes both models similar in their sinkage levels, the only difference being the material's feel.
Based on Our Review
When I tested this product, I found the latex layers of the Peacelily didn’t conform as closely as memory foam, but the switch up for a buoyant, bouncy feel every time I moved was worth it. I was comfortable on my side using both firmnesses without any pressure build-up on my shoulders or hips.
Pros:
- Excellent responsive for ease of movement;
- Excellent cooling qualities for heat dispersion;
- Excellent pressure relief due to the cushioning latex layers.
Cons:
- Slightly expensive price point;
- Non-removable cover.
Best for Restless Couples — Koala Mattress
Highlights
- The Kloudcell comfort layer absorbs a high level of motion, helping light sleepers stay asleep with fewer disturbances;
- The comfort layers adapt slowly to weight, cradling your body with a more traditional memory foam feel;
- This model has robust edges that make getting in and out of a king-size bed easier.
The Koala is my best king-size mattress in Australia for restless couples due to its exceptional motion isolation, slow-adaptive Kloudcell technology, and durable edges. A king-size mattress means you’re likely sharing the bed, which means more jostling from movement at night. The Koala can easily save you from these nightly disturbances with its comfort layers. This model can absorb a high level of motion thanks to its Kloudcell layer. In light of my tests, I noticed it took only 2 inches for the glass of water to react to my compressions, which is incredibly low. Both sides were similar, with the firm side reacting 0.5 inches further away from the glass. My partner could toss and turn, and I wouldn’t feel a thing.
The Koala’s medium-firm side had 6 inches more isolation than the Peacelily. That makes the Koala the better option for restless couples using a king-size mattress.
Some of the best king-size mattresses have that well-balanced traditional memory foam feel. That’s how I would describe the Koala. From my tests, its Kloudcell layer and zoned base took 0.7 seconds to bounce back from compressions on its medium-firm side. I noticed a distinct body-cradling feeling when lying on this side, letting me slowly sink in for excellent pressure relief. This model is slower than the Emma Comfort by 0.5 seconds, which means the Koala is better for sleepers who want a traditional memory foam feel.
Firm edges are a must to use the entire width of a king-size mattress. When I was testing this mattress, I was impressed at its compressions of just 3.5 inches on its medium-firm side and 3.2 inches on its firm side. This is much less than the recommended maximum of 4 inches, and I was stable and not at risk of slipping off while lying on the edge. The Koala’s medium-firm side offers edges stronger than the Peacelily’s medium side by 0.8 inches, making the Koala the better option if you are a sleeper wanting more support across the width of your mattress.
Based on Our Review
When testing this mattress on my side, I was comfortable on both firmnesses. There was enough sinkage that my weight was pleasantly spread over a wider area, relieving pressure from my shoulders and hips.
Pros:
- Excellent motion isolation for restless partners;
- Excellent edge support for using the entire width of the king-size bed;
- Good firmness to encourage healthy spinal alignment.
Cons:
- Non-removable cover;
- Too hot for sleepers who sleep on the hot side.
Best Modern Memory Foam Option — Emma Comfort Mattress
Highlights
- Airgocell memory foam is cradling, molding to your body for adequate pressure relief;
- The comfort and high-density zoned base layers are responsive, reacting quickly for a modern memory foam feel;
- The cover can be removed via zippers in a few seconds, keeping your sleeping space fresh.
The Emma Comfort is my best modern memory foam option for king-size mattresses due to its fast-acting foam, excellent sinkage, and high bounce level. The Emma Comfort is a perfect option for sleepers who want ease of movement across the width of their king-size mattress. From my review, the Emma Comfort took only 0.2 seconds to recover from compressions completely. Despite its cloud-like sinkage, I could get in and out of bed without feeling restricted. The Emma Comfort was 0.5 seconds faster at bouncing back than the Koala on its medium-firm side, which means the Emma Comfort is better suited to sleepers who enjoy unrestricted movement and a modern feel to their mattress.
The Emma Comfort offers the best of both worlds with its memory foam, which is highly sinkable and fast-acting. When testing this model, I measured a sinkage of 2.2 inches, and I was incredibly comfortable on my side. My weight was evenly redistributed for a cloud-like feel, and I could still enjoy switching positions quickly despite the deep cradling effect. This model has 0.15 inches more sinkage than the Koala on its medium-firm side, making the Emma Comfort better suited for effective, deep-penetrating pressure relief.
The Emma Comfort also offers a high bounce level, making getting around a large king-size mattress even easier. From my tests, the Emma Comfort’s Airgocell foam and base layers had a total bounce level of 11.5 inches. I noticed a bit of spring every time I shifted or got into bed, making fast movements easier. The Emma Comfort had 1.74 inches higher bounce than the Peacelily, despite the Peacelily being made of latex. That means the Emma Comfort is a memory foam mattress with remarkable bounce that suits sleepers who need a responsive king-size mattress.
Based on Our Review
Drawing from my test, I found the Airgoell foam thick and contouring, providing enough well-balanced cradling so I didn’t feel any pressure build-up. My shoulders and hips were comfortable and free of tension.
Pros:
- Good pressure relief for tension-free sleeping;
- Easy-to-remove cover;
- Excellent fast-acting foam for ease of movement.
Cons:
- Too soft for heavier sleepers over 230 pounds;
- Too hot for sensitive sleepers.
Why You Should Trust Me
I have examined many mattresses over the years, analyzing trends and technology in the evolving mattress industry. When I review my mattresses, my tests use quantifiable data to determine their quality. I test for comfort, pressure relief, support, and reliable edges. Other factors I also measure include cooling technology and bonuses like being able to remove the cover.
When determining the best king-size mattress, they need excellent pressure relief, support, and firm edges to ensure the entire width can be used. During my tests, I looked at these factors carefully. Mattresses that performed well in these categories were placed higher on my list and would be better suited as my top recommendations. To learn about how I review my mattresses, you can read more about my methodology here.
Who Needs A King-size Mattress?
When it comes to the best king mattress, bigger is not always better. A king-size mattress may not be necessary for everyone. Smaller mattress options may be more suitable for smaller bedrooms or people who don't need much sleeping space.
However, the bulk of sleepers prefer a king-size mattress(1) because of its obvious benefits when you share a bed with a partner. It gives each person their own space to sleep without feeling cramped. It's also great for people who like to spread out when they sleep. Additionally, a king-size mattress can make a bedroom look bigger and more luxurious!
I recommend King size mattresses for partners where one or both are restless sleepers. However, the way to maximize this extra space is by opting for a king size mattress with good motion isolation.
Also Read: How to store a mattress.
King Mattress Review: How To Choose A King-size Mattress
Shoppers on the hunt for a king-size mattress must consider some important factors. These include:
Sleeping Position
This is a crucial factor people consider when purchasing a king-size mattress or any mattress at all.
Here is why:
Those who sleep on their sides will want a softer mattress to conform to their curves. This is excellent for sleep quality, as side sleeping has been considered one of the best positions for sleepers to get better rest, especially on their right side, when sleeping on a king-size mattress (2). On the other hand, back sleepers will want a firm mattress that offers less sinkage so that their spines remain aligned. The same applies to those who sleep on their stomachs.
Memory foam or latex mattresses can be good options for people who sleep on their back or side, while innerspring mattresses are better suited for those who sleep on their stomachs.
Looking for a top-quality memory foam mattress? Be sure to check out some like these.
Mattress Build Material
The mattress material remains one of the most important factors when making purchase decisions. The right material will result in a mattress that is comfortable and breathable. It should also be durable and long-lasting.
I like to prioritize cooling for any mattress I want. Since the mattress build and construction material contributes a lot to its cooling features, it helps me streamline my choice to one or two mattress materials. You can apply this tip to any feature you prioritize in a mattress.
Bedroom Size
A king-size mattress will take up a lot of space, so one must ensure there is enough room for it. In the absence of ample real estate, other mattress sizes will make a more fitting choice. This makes sense, as most rooms are typically smaller and are ideal for queen-size mattresses. According to Statistica, king-size mattresses were the second-most popular mattress, topped only by queen-size mattresses (3).
Also Read: Best Queen Mattress in Australia
Budget
King mattresses can be expensive. Hence, it is always smart to have a clear idea of the mattress one can afford. Also, the most expensive is not always the most comfortable or durable.
Having said that, this is one area where one can splurge if one enjoys comfortable and luxurious sleep every night.
As expensive as king mattress sizes are, they do not guarantee optimal comfort. Keeping this in mind, I recommend exploring the sleep trial period of mattresses to get the perfect fit.
F.A.Q.
What are the benefits of a king-size mattress?
A king-size mattress provides plenty of space for couples or individuals who like to spread out. It can also be a good choice for people who need extra room for pets or children.
What are the specs on a king-size mattress?
A king-size mattress is 76 inches wide and 80 inches long.
How long does a king-size mattress last?
A king-size mattress should last around 10 years. However, this will vary depending on the quality of the mattress and how often it is used.
Conclusion
A king mattress is often a proud addition to any bedroom, but making the best choice can be tough. Check out our top picks for the best king-size mattresses in Australia to help you decide on the perfect mattress for your sleeping space.
In my opinion, the Ergoflex 5G is my best king-size mattress as I found its pressure relief balanced and cradling. I was comfortable on my back and had enough support for my spine to stay aligned. The visco-elastic foam redistributes weight and keeps your hips, lumbar, and neck, suiting sleepers who want a firm, well-balanced surface. The cover is also cool to the touch for comfortable, well-rounded sleep.
Start your journey today to quality sleep with the best king-size mattress in Australia.
Do you have questions or comments about king-size mattresses? We'd love to hear from you, so please comment below.
References
- Alexander Kunst. (2019, Sept 3). Width of bed used by U.S. adults 2017, by age group. Retrieved from https://www.statista.com/statistics/673201/mattress-size-among-us-adults-by-age-group/#:~:text=Almost%20a%20half%20of%20American,adults%20in%20the%20United%20States.
- NIH National Library of Medicine (2022.) The Relationship between Sleeping Position and Sleep Quality: A Flexible Sensor-Based Study. Retrieved from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9416198/.
- Statistica (2023.) How wide is the bed you mainly sleep on at home? Retrieved from: https://www.statista.com/statistics/673201/mattress-size-among-us-adults-by-age-group/.
Allana Wass is the Co-Founder and Editor-in-chief at Comfybeddy. She was trained at the Spencer Institute to become a Certified Sleep Science Coach and has been featured in VeryWellMind, U.S. News, and Bustle. She has tested over 50 sleep products, which include mattresses, mattress toppers, and pillows. She has spent countless hours researching the mattress industry and learning about its cutting-edge technology for over four years, helping you improve your sleep. With her wealth of experience, she thoroughly reviews mattresses and other sleep products to give the best recommendations for each kind of sleeper.
Our research
45
Mattresses Considered
150
Hours of Research
2
Sleep Experts Consulted
How often should I change my king-size mattress?
The lifespan of a mattress can vary, but a general rule of thumb is to consider replacing your king-size mattress every 8 to 10 years. Of course, factors like mattress quality, usage, and personal comfort preferences play a role. Keep an eye out for signs of wear and tear, sagging, or changes in your sleep quality—it might be a cue that it’s time for a mattress upgrade.
Could you recommend any king-size mattresses that truly excel in isolating motion? My goal is to create a sleep haven where I can minimize any disturbances caused by my partner’s nighttime movements.
I’d recommend the Koala mattress, especially if you’re looking to minimize disruptions from your partner’s movements at night. The Koala stands out for its exceptional motion isolation, thanks to its slow-adaptive Kloudcell technology and sturdy edges. Since a king-size bed typically means sharing with a partner, you’ll appreciate how well this mattress absorbs motion, ensuring you both enjoy a peaceful night’s sleep. During my tests, I observed that it only took a mere 2 inches for a glass of water to react to compressions, which is impressively low.