King Split Marshall® Boxsprings Handcrafted Foundations Mattress Accessories

A king box spring is almost always built as two split halves (each 38″ × 80″ — the same footprint as a Twin XL) that sit side by side under your king mattress (76″ × 80″). The split design makes a large king foundation easy to deliver, carry up stairs and set up, and it's exactly what a split-king adjustable base needs so each side can raise and lower independently. Shop split king box springs and foundations matched to Sealy, Serta, Beautyrest, Simmons, Stearns & Foster and more — free delivery across Canada. • What it is: a king box spring built as two 38″ × 80″ halves (each a Twin XL footprint) • Together they support a standard king mattress (76″ × 80″) • Easier to deliver and carry up stairs than a one-piece foundation • Required for split-king adjustable bases (each side adjusts independently) • Brands: Sealy, Serta, Beautyrest, Simmons, Stearns & Foster, Springwall, Galaxy & NM • From $176 — free Canada-wide delivery
Marshall® boxsprings and foundations are handcrafted in Canada to give your mattress a stable, supportive base. Choose a low-profile 6 inch, high-profile 9 inch or slim 2 inch posture board to set your ideal bed height, with split options for larger sizes. Built to last and backed by a 10-year warranty with free next-day delivery in Toronto.

Complete your sleep setup with pillows, toppers, protectors, and more. These mattress accessories enhance comfort and extend mattress life.

King Split Marshall® Boxsprings Handcrafted Foundations Accessories

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MARSHALL® Boxspring - High Profile 9"
LIMITED STOCK NEW ARRIVAL
Kiln-Dried Wood Foundation
Classic 9″ High Profile
Pairs With Any Mattress
OEKO-TEX® Certified Cover
FSC-Certified Wood
10 Year Warranty
Made In Canada
King Split $865
Compare at $1,399
Backorder Available
On Display:
Estimated free delivery on Tue, Aug 18 M5H 2N1
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MARSHALL® Boxspring - Low Profile 6"
LIMITED STOCK NEW ARRIVAL
Kiln-Dried Wood Foundation
Low 6″ Profile
Full-Frame Support
Pairs With Any Mattress
OEKO-TEX® Certified Cover
10 Year Warranty
Made In Canada
King Split $865
Compare at $1,399
Backorder Available
On Display:
Estimated free delivery on Tue, Aug 18 M5H 2N1
View Details
MARSHALL® Boxspring - Posture Board 2"
LIMITED STOCK NEW ARRIVAL
Kiln-Dried Wood Platform
Slim 2″ Profile
For Platform & Slatted Beds
OEKO-TEX® Certified Cover
FSC-Certified Wood
10 Year Warranty
Made In Canada
King Split $865
Compare at $1,399
Backorder Available
On Display:
Estimated free delivery on Tue, Aug 18 M5H 2N1
View Details

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