Quick Answer: Costco's split king options are limited, mostly Novaform and occasional Beautyrest models sold as twin XL pairs, ranging from $800 to $2,000 for the set. Selection rotates seasonally and may not be available when you need it. Local mattress stores generally stock more split king options year-round and let you try them first.
Brad, Owner, 40+ years of experience: "We have been helping Brantford families sleep better since 1997. Every customer gets personal attention, honest advice, and the kind of follow-up service you just do not get from big box stores."
Split king mattresses have become increasingly popular with Canadian couples who want independent sleep surfaces without separate beds. The concept is simple: two twin XL mattresses placed side by side on a king frame, often paired with a split adjustable base so each partner can adjust their side independently. But finding the right split king setup at Costco can be surprisingly tricky.
What Exactly Is a Split King Mattress?
Split King Dimensions
A split king consists of two twin XL mattresses (each 38" x 80") placed side by side to create a king-size sleeping surface (76" x 80"). Standard king mattresses are 76" x 80" as a single piece. The split king occupies the same footprint but allows complete independence between sides.
The key advantage is that each partner gets their own mattress, their own firmness level, their own motion isolation, and their own adjustable base controls if used with a split adjustable frame. Talia, our sleep specialist at Mattress Miracle, says split kings are the number one solution for couples with different body types or sleep preferences.
Costco Split King Options in Canada
Costco doesn't typically sell mattresses labelled "split king." Instead, you need to buy two identical twin XL mattresses and pair them yourself. Here's what's typically available:
Novaform Twin XL
Price: $350-$500 each ($700-$1,000 for the pair) | Memory foam construction
Available online, seasonally in-warehouse
Beautyrest Twin XL
Price: $500-$700 each ($1,000-$1,400 for the pair) | Pocketed coil hybrid
Limited availability, check costco.ca
Sealy Posturepedic Twin XL
Price: $400-$600 each ($800-$1,200 for the pair) | Innerspring construction
Seasonal availability
Costco Split King Limitations
- No mixed firmness You're buying two identical mattresses, so both partners get the same feel
- Seasonal availability Twin XL models rotate in and out, making replacement matching difficult
- Limited selection Only 2-4 twin XL options at any given time
- No pairing guidance Costco staff won't help you match mattresses to adjustable bases
Who Actually Needs a Split King?
A split king is ideal if
- You and your partner have different firmness preferences (one likes firm, the other soft)
- One partner needs an adjustable base for medical reasons (acid reflux, sleep apnea, circulation)
- Significant weight differences between partners affect how the mattress performs
- One partner tosses and turns frequently, disturbing the other
- You want separate mattress lifespans so you can replace one side at a time
A regular king may be better if
- Both partners are happy with the same firmness level
- You don't plan to use an adjustable base
- You prefer no gap or seam in the middle of the bed
- Budget is a primary concern (one king is cheaper than two twin XLs)
Split King: Pros and Cons
| Pros | Cons |
|---|---|
| Independent firmness for each partner | Gap/seam down the middle |
| Zero motion transfer between sides | Higher total cost than single king |
| Works with split adjustable bases | Need king-sized bedding (sheets can shift) |
| Replace one side without buying both | Fewer model options in twin XL size |
| Easier to move (two lighter pieces) | Need a gap filler or connector for the seam |
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Split King Pricing: Costco vs Mattress Miracle
| Specification | Costco Twin XL Pair | Restonic ComfortCare Twin XL Pair |
|---|---|---|
| Price (two mattresses) | $800-$1,400 | $1,750 |
| Coil count per mattress | ~600-800 | 690 |
| Coil type | Varies by model | Individually wrapped |
| Mix firmness levels | No, same model both sides | Yes, different models per side |
| Adjustable base compatible | Depends on model | All models compatible |
| Try before buying | Limited | Full showroom testing |
| Delivery | Self-transport | White glove delivery and setup |
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Better Split King Options at Mattress Miracle
Brad, our senior consultant, explains the biggest advantage of buying a split king from a specialty retailer: "At Costco, you're buying two identical mattresses. At Mattress Miracle, we can pair different firmness levels, a medium on one side and a firm on the other. We match each mattress to each partner's body type and sleep position. That's something you simply can't do at a warehouse."
Restonic Split King Options
- ComfortCare Twin XL pair ($1,750) 690 individually wrapped coils per mattress, excellent entry point for couples wanting independence
- Revive Reflections ET Twin XL pair ($4,790) 1,200 coils per mattress, flippable dual-sided design, each partner can choose which side faces up
- Mix and match Combine any two Restonic twin XL models for a custom split king
Frequently Asked Questions
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Call 519-770-0001Does Costco sell split king mattresses?
Costco doesn't sell split king mattresses as a labelled product. To create a split king from Costco, you buy two twin XL mattresses of the same model. Availability of twin XL sizes varies seasonally, and you're limited to choosing the same model for both sides.
How do you fill the gap in a split king?
A split king gap filler (also called a bed bridge or mattress connector) is a foam wedge that sits in the seam between the two twin XL mattresses. These cost $20-$50 and effectively eliminate the gap. A king-sized mattress topper placed over both mattresses can also smooth the transition.
Do split king mattresses need special sheets?
You can use standard king-sized flat sheets and a king comforter. For fitted sheets, you have two options: use two twin XL fitted sheets (one per mattress) or buy a split king fitted sheet designed with elastic on all sides to hold both mattresses together. Twin XL fitted sheets are easier to find and wash.
Can I mix different mattress brands in a split king?
Yes, you can mix brands and firmness levels in a split king. This is actually one of the main advantages of the format. At Mattress Miracle, we help couples select different Restonic models for each side based on individual sleep preferences, body weight, and sleeping position.
Is a split king the same size as a regular king?
Yes, a split king uses two twin XL mattresses (each 38" x 80") which together equal a standard king size (76" x 80"). All king-sized bed frames, headboards, and bedding work with a split king setup.
Do I need a split adjustable base for a split king?
Not necessarily. You can place a split king on any king-sized flat frame or platform. However, if you want independent adjustment (each partner controls their side), you'll need either a split king adjustable base or two twin XL adjustable bases side by side. The independent adjustment is one of the main reasons people choose split kings.
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Mattress Miracle
441 1/2 West Street, Brantford
Phone: (519) 770-0001
Hours: Mon-Wed 10-6, Thu-Fri 10-7, Sat 10-5, Sun 12-4
Our team has 38 years of experience helping customers find the right sleep solution. Call ahead or walk in any day of the week.
Sources
- Jacobson BH, Boolani A, Smith DB. Changes in back pain, sleep quality, and perceived stress after introduction of new bedding systems. J Chiropr Med. 2009;8(1):1-8. DOI: 10.1016/j.jcm.2008.09.002
- Radwan A, Fess P, James D, et al. Effect of different mattress designs on promoting sleep quality, pain reduction, and spinal alignment in adults with or without back pain. Sleep Health. 2015;1(4):257-267. DOI: 10.1016/j.sleh.2015.08.001
- Kovacs FM, Abraira V, Peña A, et al. Effect of firmness of mattress on chronic non-specific low-back pain: randomised, double-blind, controlled, multicentre trial. Lancet. 2003;362(9396):1599-1604. DOI: 10.1016/S0140-6736(03)14792-7
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