Choosing a mattress is not just about finding one that feels comfortable for a few minutes. The right mattress should provide a balance of support and pressure relief throughout the night, and your preferred firmness can make a real difference.
But should you choose a soft, medium, or firm mattress? The answer depends on more than personal preference. Your sleeping position, body shape, weight, and the way a mattress supports your body all play a part.
This mattress firmness guide explains what the different firmness levels mean and how to choose the right feel for your sleep position.
What Does Mattress Firmness Mean?
Mattress firmness describes how hard or soft a mattress feels when you lie on it. It is different from support.
A firm mattress is not automatically more supportive, and a softer mattress is not necessarily lacking in support. A well-designed mattress can provide a softer comfort layer while still having a stable support core underneath.
It is also worth remembering that firmness is not completely standardised. A mattress described as "medium-firm" by one manufacturer may feel different from another. This is why the construction and materials matter just as much as the firmness label.
What Firmness Is Best for Your Sleeping Position?
Your usual sleeping position is one of the best places to start when choosing mattress firmness.
Side Sleepers
Side sleepers generally put more pressure on their shoulders and hips because these areas carry more of the body's weight against the mattress.
A medium or medium-firm mattress with some cushioning can help relieve pressure while still providing adequate support. An extremely firm mattress may feel uncomfortable around the shoulders and hips, particularly if you spend most of the night on your side.
If you are a dedicated side sleeper, look for a surface that allows your shoulders and hips to sink slightly without letting the rest of your body sag.
Back Sleepers
Back sleepers generally benefit from a supportive surface that allows the spine to remain in a relatively neutral position.
A medium-firm to firm feel can work well because it provides stability beneath the heavier areas of the body while still allowing some cushioning. However, the goal isn't necessarily to choose the hardest mattress available.
The important thing is to find a balance between support and comfort rather than simply choosing a mattress because it is labelled "firm".
For more information about choosing a mattress for spinal support, see our guide to the best mattress for back pain in Australia.
Stomach Sleepers
Stomach sleepers generally need a mattress that prevents the hips and midsection from sinking too deeply.
A medium-firm or firmer mattress can help provide the stability needed to keep the body in a more comfortable position. A mattress that is too soft may allow the midsection to sink, which can leave you feeling uncomfortable when you wake up.
If you regularly change positions during the night, however, you may prefer a more balanced firmness rather than choosing a very firm mattress specifically for stomach sleeping.
Soft vs Medium vs Firm Mattresses
There is no single firmness that is right for everyone.
Soft: Provides more cushioning and lets the body sink deeper into the comfort layers. It may suit people who prefer a plush feel or need more pressure relief.
Medium: Offers a balance between cushioning and support and can suit a wide range of sleepers, particularly combination sleepers.
Medium-firm: Provides a stronger feeling of support while retaining some pressure relief. It is a popular choice for back sleepers and people who prefer a more supportive surface.
Firm: Creates less sink and a more stable sleeping surface. It may suit people who prefer sleeping on top of the mattress or need greater resistance around the hips and midsection.
Your body weight can also influence how firm a mattress feels. The same mattress may feel firmer to a lighter sleeper and softer to a heavier sleeper because the amount of pressure placed on the comfort layers is different.
Firmness and Support Are Not the Same
This is one of the most important things to understand before buying a mattress.
A mattress can feel soft on the surface while still providing strong support underneath. For example, a mattress can combine a responsive support system with comfort materials designed to cushion pressure points.
Felice mattresses use 5-zone ergonomic support, with targeted support for areas such as the shoulders, hips, and lower back. The range also focuses on pressure relief, breathability and motion isolation.
The Felice Green combines pocket springs with a natural latex comfort layer, while the Felice Hybrid combines responsive pocket springs with memory foam. These different constructions can create noticeably different feels even though both are designed around support and comfort.
You can also compare the two in our detailed Felice Green vs Felice Hybrid mattress comparison.
How Do You Know If Your Mattress Is Too Soft or Too Firm?
Your body can often give you useful clues.
If a mattress is too soft, you may feel that your hips or midsection sink excessively, making it difficult to turn or get comfortable.
If it is too firm, you may notice pressure around your shoulders and hips, particularly when sleeping on your side.
A mattress should feel supportive without creating uncomfortable pressure points. Give yourself some time to adjust to a new mattress rather than judging it solely by the first few minutes.
Does Your Mattress Size Affect Comfort?
Firmness is only one part of choosing the right mattress. Size matters too, particularly if you share your bed.
Australian mattress sizes are not identical to US or UK dimensions, so it is worth checking measurements before ordering. Our Australian mattress size guide covers standard dimensions and the actual dimensions of Felice mattresses.
For couples, mattress construction can also be important. If one person moves frequently during sleep, motion isolation can help reduce disturbances between partners.
How to Choose the Right Mattress Firmness
If you are unsure where to start, consider these four questions:
- What position do you sleep in most often?
- Do you prefer a plush, balanced or supportive feel?
- Do you experience pressure around your shoulders or hips?
- Are you sharing the mattress with a partner who has different preferences?
From there, compare the mattress construction, not just the firmness description.
If you are planning to purchase online, our guide to how to buy a mattress online in Australia covers other factors worth considering before placing an order.
The Right Firmness Is About Balance
There is no universal "best" mattress firmness. The right choice is the one that gives you enough support while remaining comfortable for your preferred sleeping position.
Side sleepers may prefer more cushioning around the shoulders and hips, while back and stomach sleepers often prefer a more supportive feel. Combination sleepers may find a balanced medium or medium-firm mattress easier to live with.
Rather than choosing the firmest or softest option available, focus on support, pressure relief, sleeping position, and overall comfort. That combination is a much better starting point for finding a mattress you'll be happy to sleep on night after night.
