Double vs King Size Beds and Mattresses: Which Is Right for You?

When it comes to upgrading your sleep setup, one of the most important decisions you'll make is choosing the right bed and mattress size. At Bensons for Beds, we know that comfort, space, and lifestyle all play a role in finding your perfect fit. Two of the most popular choices for couples and individuals alike are double beds and king size beds — but which one is best for you?

In this guide, we’ll break down the key differences between double and king size beds and mattresses, so you can rest easy knowing you’ve made the right choice.

What’s the difference in size?

Let’s start with the basics:

Bed Size	Mattress Dimensions (cm)	Mattress Dimensions (ft)
Double	135 x 190cm	4’6” x 6’3”
King Size	150 x 200cm	4’6” x 6’6”

The king size bed is 15cm wider and 10cm longer than a standard double. While that might not sound like much, it can make a significant difference, especially if you’re sharing the bed or are taller than average.

Key considerations

When deciding between a double and a king size mattress, here are the top things you need to think about.

1. Sleeping space

Double beds are ideal for solo sleepers or couples who don’t mind a cosier setup.

King size beds offer more room to stretch out and can help reduce sleep disturbances from a restless partner.

Top tip: If your partner tosses and turns or you both enjoy extra personal space, a king size bed could lead to better quality sleep.

2. Bedroom size

Before you buy, measure your room. A king size bed needs more floor space, not just for the frame, but also for walking around and ensuring other essential furniture items still fit.

Double beds work well in standard-sized or guest bedrooms.

King beds are best suited to larger master bedrooms (ideally 4m x 4m or more).

Pro tip: Don’t forget to account for bedside tables, wardrobes, and opening drawers or doors.

3. Mattress & bedding cost

Double mattresses and bedding are generally more affordable and widely available.

King size options may cost more, but offer enhanced comfort and durability, — especially if you invest in high-quality materials like memory foam or pocket springs.

At Bensons for Beds, we offer a wide range of double and king size mattresses to suit every budget and sleep style—from firm orthopaedic to cloud-like hybrid models.

Who should choose a double bed?

A double bed is perfect for:

• Solo sleepers who want more room than a single
• Couples with limited bedroom space
• Guest rooms and teenagers’ bedrooms
• Budget-conscious shoppers

Who should choose a king size bed?

A king size bed is ideal for:

• Couples who value space and sleep quality
• Taller individuals who need extra legroom
• Families with young kids or pets who sneak into bed
• Master bedrooms with ample space – though those with enough space may want to consider king size vs super king beds instead.

Benefits of choosing a bigger bed

Bigger beds are a better choice for most scenarios if your budget and bedroom size can accommodate one. Here, we explain why bigger is often better when it comes to bed and mattress size.

1. More personal space

• A larger bed gives each sleeper more room to move around freely during the night promoting better comfort.
• Reduces the chances of disturbing your partner when turning over during the night.
• Ideal for couples who prefer their own sleeping space, or have different sleep styles (e.g. one is a sprawler, the other sleeps curled up).

2. Better sleep quality

• Less disturbance means fewer awakenings, helping you stay in deeper stages of sleep longer.
• More space allows you to find your most comfortable position, which can in turn reduce the amount of tossing and turning you do.

3. Great for taller people

• Bigger beds (especially those longer than standard double beds) provide extra legroom, making them perfect for taller sleepers.
• No more cold feet hanging off the edge of the bed!

4. Family-friendly

A king or super king bed is ideal if you:

• Have young children who occasionally co-sleep
• Share the bed with a pet
• Want more space for weekend lie-ins with the whole family

5. Health benefits 

More room helps with certain health conditions, such as:

• Joint pain or arthritis: by enabling a more supportive, comfortable sleeping posture
• Sleep apnoea or snoring: larger beds allow for better positioning and sometimes reduce symptoms
• Restless leg syndrome: space to move without disturbing a partner

6. Luxury and comfort

A bigger bed often just feels more luxurious — like a hotel experience every night.

You can combine it with premium mattresses, memory foam toppers, and high-thread count bedding for the ultimate sleep sanctuary.

7. Mental and emotional benefits

Knowing you have your own space can create a more peaceful, relaxed mindset before bed. Less tension over sleep disruptions can lead to happier relationships between couples.

8. Future-proofing your sleep

• Investing in a larger bed now can save you from future upgrades.
• Ideal if your circumstances change: like moving to a bigger house, getting a partner, or having children.

Choosing the right mattress

Whether you go for a double or king, your mattress choice matters just as much as the size. At Bensons for Beds, we recommend visiting one of our stores to try out our SleepPRO® technology — a free in-store experience that matches you up with your ideal mattress based on your sleep profile.

King size vs double beds: final thoughts

Choosing between a double and king size bed comes down to personal preference, space, and budget. A double bed offers practicality and affordability, while a king size bed delivers superior comfort and room to move.

Still unsure? Let our sleep experts help you find your dream bed in-store or online. At Bensons for Beds, we’re here to make sure every night is your best night’s sleep.

Explore our collection of double beds and king size beds today, or pop into your nearest Bensons for Beds showroom to try before you buy.