A woman buying mattress and bed base

Double Bed Base and Mattress: How to Choose the Right Combination

A Double bed and mattress sits at that practical middle point in the Australian bed sizes range — big enough for single adults to sprawl, small enough to fit in bedrooms where a Queen would eat into walking clearance. It's a natural upgrade for teens moving on from a single mattress, the go-to size for guest rooms, and a workable option for couples who like sleeping close together. But choosing the right Double bed setup means more than picking a size. You need a mattress that suits how you sleep, a bed base that supports it properly, and — if you're buying both — a coordinated pairing that works together from the start. This guide walks you through the full Double bed decision: whether Double is the right size for you, how to choose the right mattress and bed base, and where the Koala range fits.

A Double bed base and mattress measure approximately 138cm × 188cm in Australia. They're a popular choice for single adults, teenagers, guest rooms and smaller bedrooms — while some couples who like sleeping close together also find them suitable. When choosing a Double bed, consider your sleeping space, preferred mattress feel, bedroom size, and whether a compatible bed base provides the support your mattress needs.

Key takeaways

  • Double dimensions in Australia: 138cm × 188cm — bigger than a King Single, smaller than a Queen

  • Double works for: single adults, teens, guest rooms, smaller bedrooms, and couples who like sleeping close together

  • Double vs Queen is the most common decision point — Queen (153cm × 203cm) suits couples wanting long-term room to spread out

  • Foam mattresses need slat spacing of 7-8cm or less — verify this before pairing a mattress with a bed base

  • Koala offers 4 Double mattresses + 4 Double bed bases — all designed to work together

  • Coordinated bundles simplify the purchase — 120-day mattress trial + 10-year mattress warranty + 5-year bed base warranty

  • Double (AU) is not the same as Full (US) — Full is 137cm × 191cm; slightly different dimensions

What is a Double bed base and mattress?

A Double bed base and mattress is the pairing of a Double-sized mattress with a Double-sized bed base — both measuring approximately 138cm × 188cm in Australia (per Koala's own Double collections). Sometimes sold together as a coordinated bundle, sometimes purchased separately, the pairing forms the foundation of a complete sleep setup.

Double bed dimensions in Australia sit between King Single (107cm × 203cm) and Queen (153cm × 203cm) — noticeably wider than a King Single but narrower than a Queen, with the same length as a Single. This makes Double a practical choice for bedrooms where a Queen would feel oversized but a Single would feel cramped.

Who Double beds typically suit:

  • Single adults wanting more room than a King Single

  • Teenagers upgrading from a single mattress

  • Guest rooms accommodating single or short-stay couples

  • Smaller main bedrooms in apartments or studios

  • Couples who like sleeping close together (per Koala's positioning on the Double Bed Bases collection page)

This guide walks through whether Double is the right size for your situation, then covers how to choose the right mattress and bed base for a comfortable, well-supported setup.

Is a Double bed the right size for you?

Before you start looking at mattress specs or bed base styles, work out whether Double is the right size for your situation. The audiences below all commonly buy Double, but for different reasons.

Single adults. A Double gives you noticeably more room than a King Single. If you sprawl, share with pets, or have overnight guests occasionally, Double works well. If you already know you want maximum solo space, Queen is worth considering.

Teenagers. Double is often the natural upgrade from a single mattress as teens grow — it lasts through the late-teen years and into early adulthood without needing another size upgrade. Most teenagers don't need Queen, and Double fits better in typical teen bedrooms.

Guest rooms. Double accommodates single guests comfortably and is workable for couples on a short-stay basis. It's also more space-efficient than Queen if the guest room doubles as an office, study, or storage space.

Smaller bedrooms. Studios, second bedrooms, garden studios, and compact main bedrooms all suit Double better than Queen. A Queen bed in a small bedroom eats into walking clearance around the bed; Double leaves room for bedside tables and everyday movement.

Couples. Koala positions Double as suitable for couples "who want to sleep close together" — workable if you and your partner naturally sleep close, or if you need to fit a bed in a compact bedroom. Not the best long-term choice if you and your partner want room to spread out during the night.

How Double compares to other Australian bed sizes

Bed size

Dimensions (cm)

Best suited for

Single

92 × 188

Kids' rooms, tight guest rooms, single sleepers with minimal space

King Single

107 × 203

Older kids, taller single sleepers wanting extra length

Double

138 × 188

Single adults, teens, guest rooms, cosy-sharing couples, smaller bedrooms

Queen

153 × 203

Couples wanting long-term room to spread out, taller sleepers (203cm length)

For the comprehensive framework covering all Australian bed sizes, see our mattress sizes Australia guide.

Double vs Queen: which should you choose?

This is the most common decision point for Double shoppers. Both sizes work — the right choice depends on your specific situation. Six factors to consider:

Room size. Double fits comfortably in bedrooms with 3m × 3m or less floor space, while Queen typically needs at least 3.5m × 3.5m to leave walking clearance on both sides. Measure your bedroom before assuming Queen will fit — the extra 15cm width matters when there's a wall on one side.

Budget. Double is typically the more accessible price point for both the mattress and the bed base. If your budget is a real constraint, Double gives you more flexibility to invest in the mattress quality rather than the mattress size.

Sleeping space per person. For couples sharing, Double gives each person about 69cm of width, while Queen gives each about 76cm. That extra 7cm per person makes a real difference over months and years of sharing a bed.

Future needs. Queen accommodates life changes better — a new partner, a growing height, a shift in sleeping style. Double works for now but can feel restrictive if your situation changes.

Bedroom layouts. In a smaller bedroom, Queen dominates the room visually and can leave no space for bedside tables or a chest of drawers. Double leaves room for the surrounding bedroom furniture.

Length considerations. Double is 188cm long — sleepers over 183cm may find their feet overhang. Queen is 203cm, which accommodates most heights.

Choose Double when:

  • Your bedroom footprint is limited

  • Budget is a real factor

  • You're a solo sleeper wanting more room than a King Single

  • You're upgrading from a teenager's single mattress

  • You and your partner naturally sleep close together

Choose Queen when:

  • Your bedroom fits it with walking clearance

  • You and your partner want long-term room to spread out

  • You're over 183cm regularly

  • You're planning for future needs (new partner, taller adults, changing sleep styles)

If you decide Queen suits you better, explore Koala's Queen Mattresses collection (⚠️ URL to verify before publication).

Choosing the right Double mattress

Once you've committed to Double, the mattress decision comes down to five features. Match these to your sleep style, not to the size — Double buyers include everyone from single adults to teens to cosy-sharing couples, and each has different priorities.

Firmness. Most Double buyers do well with medium to medium-firm feel — enough contouring for side sleeping, enough support for back sleeping, and firm enough to keep hips from sinking during stomach sleeping. For a deep dive on how firmness affects sleep quality, see our firmness and sleep recovery guide.

Pressure relief. Matters most for single sleepers who spend a lot of the night in one position — pressure-point discomfort triggers micro-arousals that shorten deep sleep. Open-cell foams (like Koala's Kloudcell®) distribute weight evenly. See our pressure relief mattress guide.

Sleeping position. Side sleepers prioritise contouring at the shoulder and hip; back sleepers prioritise lumbar support; combination sleepers benefit from fast-response foam that makes position changes effortless. For combination sleepers specifically, see our best mattress for combination sleepers guide.

Cooling. Especially important for teens (who often run warm), couples sharing a Double mattress (which generates more combined body heat than solo sleeping), and warmer Australian climates. See our breathable mattress guide.

Motion isolation. If two people share the Double bed regularly, motion isolation prevents partner disturbance. Koala's Zero Disturbance® engineering absorbs movement locally rather than transmitting it across the surface.

Koala Double mattress recommendations

All 4 Koala Double mattresses use proprietary Kloudcell® open-cell foam — engineered as a modern alternative to traditional memory foam, with faster response and better breathability.

Bedroom with a wooden bedframe, light green mattress, and matching bedding. Wooden side table, lamp, and soft beige rug complement the room.

  • Koala Plus — Cooling Gel Kloudcell® + CoolThread™ topper. Best for: hot sleepers, warmer AU climates, cosy-sharing couples wanting cooling

A bedroom with a wooden bed featuring a grey mattress and peach cushion. A round wooden side table with a white lamp is nearby. Decorative bunting hangs above.

  • Koala Luxe — 9cm Kloudcell® + 7 multi-layered support zones (per Luxe product page) + copper-infused + phase-change temperature control + Australian Cashmere blend cover. Best for: premium plush-feel preference

Koala Luxe Mattress in Queen on bed frame in modern bedroom with teal stripe and Koala label
Modern bedroom with a wooden bed frame, light grey mattress, and patterned cushions. A green chair, guitar, and cactus accent the room.

Explore the full Double mattress range →

Choosing the right Double bed base

The right Double bed base depends on your bedroom aesthetic, your storage needs, and the mattress you're pairing it with. Three main styles to choose from:

Platform bed bases. Solid or slatted base with legs — low-profile, modern look, no box spring needed. Most Koala Double bed bases are slatted platform designs, which support foam mattresses and allow airflow underneath. Best suited for: modern bedrooms, foam mattresses, apartments where under-bed clearance matters. For a deeper dive on platform vs slatted, see our platform bed guide.

Timber bed frames. Natural timber aesthetic, sturdy build, ages well. Koala examples:

  • Kirribilli Bed Base — award-winning, "maximise airflow and storage" (per product page). Warm Ash or Dark Ash finish

 

Light wood bed frame with slatted design, showing a foldable headboard. Simple, minimalist style suitable for various bedroom decors.

 

 

  • Balmain Bed Base — award-winning minimalist slatted design, Ash veneer finish, headboard optional

Single wooden bed frame with light brown finish, featuring a simple headboard and wooden slats for mattress support.

Upholstered bed bases. Fabric-covered headboard for a softer aesthetic and comfortable sitting-up-in-bed. Koala examples:

  • Paddington Bed Base — Good Design Award winner. 22% REPREVE™ recycled polyester upholstery. Warm, textured headboard

Minimalist wooden bed with an upright light grey upholstered headboard. The bed frame features a slatted wooden base.

  • Brunswick Bed Base — colourful upholstered in three finishes (Bush Walk, Corner Store, Limestone). Best for colour-forward bedrooms

Olive green fabric bed frame with a high headboard, wooden slatted base, and light wood legs. Ideal for modern bedroom decor.

How to match bed base style to your bedroom:

  • Minimalist / Scandinavian bedrooms: Kirribilli or Balmain (natural timber)

  • Cosy / textured bedrooms: Paddington (upholstered headboard, Good Design Award)

  • Colour-forward bedrooms: Brunswick (three fabric options)

  • Rental or potential-move bedrooms: any Koala base — all feature tool-free assembly for easy disassembly

What every Koala Double bed base includes:

  • FSC®-certified timber

  • Tool-free assembly (under 30 minutes per Double Bed Bases collection FAQ)

  • 5-year bed base warranty

  • Slat spacing engineered for foam mattress compatibility

Explore the full Double bed base range →

Should you buy a Double mattress and bed base together?

Buying both together has practical advantages, though it isn't the right choice for everyone.

Compatibility. Bundle purchases align mattress specifications with bed base slat spacing by design — you don't have to research whether the pairing works.

Convenience. Single purchase, single delivery window, single warranty relationship.

Coordinated look. Matched finishes and timber tones across the pairing.

One purchase. Often better overall value than sourcing components separately, though this depends on the specific bundle and current pricing.

When to buy together: you're setting up a new bedroom, replacing both simultaneously, or refreshing a room.

When to buy separately: your existing bed base is compatible with your new mattress, or you have strong specific style preferences that aren't offered as a coordinated bundle.

For the full framework on bundle buying, see the cluster:

Common mistakes when buying a Double bed

Mistake

Why it matters

Buying without measuring the bedroom

A Double bed still needs walking clearance and doorway access — measure floor space, doorway width, and stairwell access before ordering

Confusing Double (AU) with Full (US)

In Australia, this size is called Double (138cm × 188cm). US content often calls the closest size "Full" (approximately 137cm × 191cm) — similar but not identical. Always shop AU sizing for AU delivery

Assuming Double suits every couple

Double works for couples who like sleeping close together, but can feel tight for two adults wanting long-term room to spread — see the Double vs Queen framework above

Choosing the wrong firmness for the primary sleeper

Firmness should match the person who sleeps on the mattress most. If you share, consider the more sensitive sleeper's preferences

Forgetting bedroom access — doorways and stairwells

Mattresses ship compressed; bed bases arrive in flat-pack sections. Both still need to fit through your doorways and any stairwells

Not checking bed base compatibility with foam mattresses

Foam mattresses need slat spacing of 7-8cm or less — wider spacing can void the mattress warranty

Ignoring mattress depth (thickness)

Standard Double mattress depth is 20-30cm; deeper mattresses require deeper fitted sheets and change the total bed height

Buying only on price

The cheapest Double setup isn't the best value if the mattress + bed base don't suit your sleep style. Consider trial period + warranty

Assuming Koala mattresses are memory foam

Koala uses Kloudcell® — a proprietary open-cell foam, not traditional closed-cell memory foam

Skipping the mattress trial

Mattress feel takes weeks to properly assess — Koala offers 120 nights on all Double mattresses

Explore Koala's Double mattresses and bed bases

If you've decided Double is the right size for your bedroom, Koala offers a coordinated Double range across mattresses, bed bases, and bundles.

Double mattresses (4 options)

Koala Double Mattresses collection → — 4 mattresses in Double:

  • Koala Mattress (Core) — flippable medium-firm/firm

  • Koala Plus — cooling specialist

  • Koala Luxe — premium plush with 7-zone support

  • Koala SE — CHOICE®-Recommended entry-tier

Double bed bases (4 options)

Koala Double Bed Bases collection → — 4 adult bed bases in Double:

  • Kirribilli — award-winning slatted timber

  • Balmain — award-winning minimalist

  • Paddington — Good Design Award upholstered headboard

  • Brunswick — colourful upholstered (three finishes)

Coordinated Bedroom Bundles

Koala Bedroom Bundles collection → — any Koala Double mattress paired with any Koala Double bed base, with coordinated delivery and warranty.

What every Koala Double purchase includes

To compare in person, visit our Koala Moore Park Showroom in Sydney.

Finding the right Double bed setup

Double is the right choice when your bedroom fits it, your budget favours it, or your situation suits it — single adults wanting more room than a King Single, teens moving up from a single mattress, guest rooms, smaller bedrooms, and couples who like sleeping close together. If your room accommodates Queen and you plan to share long-term with room to spread out, Queen typically works better. Once you've committed to Double, Koala offers 4 mattresses + 4 bed bases + coordinated bundles all designed to work together, backed by a 120-day mattress trial that lets you test the setup across a full season before fully committing.

Ready to shop your Double bed setup?

Explore Koala's Double mattresses, Double bed bases, or coordinated Bedroom Bundles — all designed to work together. All Koala mattresses come with a 120-day trial and a 10-year warranty. To compare in person, visit our Koala Moore Park Showroom in Sydney.

Shop Koala Double Mattresses →

  Shop Koala Double Bed Bases →

 

 

Frequently asked questions

What size is a Double bed in Australia, and how much space do I need for one?

A Double bed base and mattress in Australia measure 138cm × 188cm. To fit a Double comfortably in your bedroom with walking clearance, look for a room with at least 3m × 3m of floor space. You'll also need to allow for bedside tables (typically 45-60cm wide each) and any additional bedroom furniture. Measure your doorways and any stairwells before ordering — mattresses ship compressed and bed bases arrive in flat-pack sections, but you still need adequate access to the room.

Is a Double bed big enough for two adults, and is it suitable for teenagers?

Double works for couples who like sleeping close together — each person gets about 69cm of width. It's tight for two adults who want long-term room to spread out (Queen gives each person about 76cm width, plus 15cm extra length). For teenagers, Double is often the natural upgrade from a single mattress — it lasts through the teen years and into early adulthood without needing another size upgrade. Most teens don't need Queen, and Double fits better in typical teen bedrooms.

What's the difference between a Double and a Queen bed?

Double measures 138cm × 188cm; Queen measures 153cm × 203cm. Queen is 15cm wider (about 7cm more per person if you share) and 15cm longer (which matters for sleepers over 183cm). Queen accommodates two adults with more room to spread out and works better for long-term shared sleep. Double is more space-efficient, more budget-friendly, and better suited to smaller bedrooms. Choose Double when your room, budget, or situation favours it; choose Queen when you have the room and want long-term flexibility.

Can any Double mattress fit any Double bed base?

Not automatically. All Australian Double mattresses and bed bases are 138cm × 188cm as standard, but you should still verify exact dimensions on both product pages before ordering — some brands vary by 1-2cm. For foam mattresses (like Koala's Kloudcell® range), also check that the bed base has slat spacing of 7-8cm or less to prevent the foam from dipping between slats. If your bed base has wider slat spacing, it can void the mattress warranty. All Koala Double mattresses and Double bed bases are designed to work together — mixing brands requires the compatibility check.

Should I buy a Double mattress and bed base together?

If you're setting up a new bedroom or replacing both at the same time, buying together simplifies the process and ensures compatibility. Coordinated bundles align the mattress and bed base by design — you get single delivery, coordinated warranty, and matched finishes. If your existing bed base is still structurally sound and compatible with the new mattress (correct size, appropriate slat spacing, no sagging or damage), buying only the mattress is usually the better-value choice. For a full framework on bundle vs separate purchases, see our are mattress and bed base bundles worth it guide.

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