How to choose a mattress: a step-by-step guide

The short answer: Make the decisions in order. Budget and size come first, because they rule out the most options. Then choose a construction (foam, hybrid, innerspring or latex), narrow the firmness using your sleeping position and body weight, and check the three things that decide how a mattress feels at 3am: heat, partner movement and edges. Before you pay, read the trial, warranty and delivery terms. The trial period, not the showroom or the product page, is where you find out whether it suits you.

Everything in this guide comes from how mattresses are built and from the terms brands publish. We do not buy mattresses to sleep on them, and nothing here depends on one person’s idea of comfortable. The point is to get you to a short list of two or three, so that the trial does the rest.

Step 1: Set a budget for the whole bed

Mattress prices in Australia are usually advertised from the smallest size a brand sells. The price that matters is the one in the size you will actually buy, and the gap between the two is different for every brand. Our size guide explains how to compare them like for like.

Then add the things that come with a new mattress:

• A bed base, if your current one is sagging, has slats too far apart, or does not meet the new mattress’s warranty conditions.
• A mattress protector. Most warranties exclude stained mattresses, so this is close to essential. See our guide to protectors.
• Sheets, if you are changing size or moving to a deeper mattress.
• Delivery and removal of the old mattress, which some retailers include and others charge for.

A budget built this way often changes the decision. A mattress that leaves no room for a base it needs is not the cheaper option.

Step 2: Choose the size before the model

Size decides price, sheets, the base and whether the bed fits the room, so settle it first. Two adults sharing a Queen get about 76 cm of width each; on a King it is about 91.5 cm each, which is close to a Single per person. Measure the room with the frame you plan to use, not just the mattress, and check stairs and doorways if the mattress will arrive flat rather than in a box.

Step 3: Pick a construction

Almost every mattress sold in Australia is one of four constructions. Each has a character, and choosing one narrows the field quickly.

Construction	What it feels like	Watch out for
All-foam	Hugs and cushions, slow to respond, very little partner movement	Holds more heat; softer edges
Hybrid (pocket springs + foam or latex)	Supportive with some bounce, easier to change position	Heavier and usually dearer than all-foam
Innerspring	Firm and springy, breathes well	Connected springs pass movement across the bed
Latex	Buoyant and responsive, sleeps cooler than memory foam	Heavy, and usually expensive

If you are choosing between the two most common options, our hybrid vs memory foam guide goes through them side by side. For what sits under the cover, see what your mattress is made of, pocket springs explained and latex explained.

Step 4: Narrow the firmness

Firmness labels are not standardised, so a “medium” from one brand can be firmer than a “medium-firm” from another. Use the label to get close, not to decide. Two things move you along the scale:

• Sleeping position. Side sleepers usually need a softer comfort layer so the shoulder and hip can sink in. Back sleepers tend to do well in the middle of the range. Stomach sleepers usually need something firmer so the hips do not sag. Our guide to sleeping positions covers each one.
• Body weight. A heavier body sinks further into the same mattress, so it feels softer. A lighter body barely compresses the comfort layer, so it feels firmer. If you are well above or below average weight, shift one step firmer or softer.

How firm should your mattress be? explains how to read the labels and what to do when two people want different things.

Step 5: Check heat, movement and edges

These three decide most complaints after the first month.

• Heat. Springs let air move; dense memory foam close to the body holds warmth. If you sleep hot, read what a mattress can and can’t do about it.
• Partner movement. Foam and pocket springs absorb most of it; connected innerspring units pass it along. Couples should read choosing a mattress for two.
• Edges. If you sit on the side of the bed to dress, or sleep near the edge, look for a reinforced perimeter. Foam edges without reinforcement compress more.

Step 6: Read the policies before the product page

The policies are where mattresses really differ, and they are the part you can check in advance.

• Sleep trial: how many nights, whether there is a minimum before you can return, who pays for collection, and whether you get a refund or only an exchange. How sleep trials really work explains the fine print.
• Warranty: how long, what depth of sagging counts as a defect, and what it requires of your base and your care. See what “10 years” actually covers.
• Delivery: boxed or flat, whether it is carried to the room, and whether old-mattress removal is offered.

Your rights under Australian Consumer Law apply on top of all of this, whichever shop you buy from. Our guide to buying online or in store explains what they cover.

Step 7: Use the trial properly

Your body needs time to adjust to a different mattress, and the first week is rarely representative. Use the mattress on the base you will keep, with a protector on from the first night, and give it a few weeks before you judge it. Note the delivery date and the trial deadline, keep the order details somewhere you can find them, and read the return conditions before the last week rather than during it.

Where to go from here

Once you have a size, a construction and a firmness range, the top rated mattresses page and the category pages — back pain, side sleepers, hot sleepers and affordable — narrow it to specific models. The comparison tool puts any of them side by side.

Common questions

What is the most important thing to get right?
Size and firmness range. A well-made mattress in the wrong firmness is still the wrong mattress, and size decides the price, the base and the bedding.

Should I buy the firmest mattress I can for back support?
No. Support comes from keeping your spine in line, and a mattress that is too firm for your position and weight can push the shoulders and hips out of line. Medium to medium-firm suits most back and combination sleepers.

How long should I give a new mattress before deciding?
A few weeks if the trial allows it. Some brands set a minimum number of nights before a return is accepted, so check that first.

Is a more expensive mattress always better?
Not necessarily. Price follows materials, construction and brand, not how well a mattress suits you. A mid-priced mattress in the right firmness will sleep better than a premium one in the wrong one.

Can I trust the firmness rating on the product page?
Use it as a starting point. Ratings are set by each brand on its own scale, so compare descriptions and construction rather than the number alone.