rigsize

Forest River Flagstaff 12ST mattress size

Years 2026Sold as Flagstaff HardsideLength 18' 4"
54 in 80 in
To scale. Dashed: a regular queen.
Main bed54 × 80 inCustom size

That isn't a standard mattress size, so order a custom size cut to your platform.

2026 Forest River Flagstaff Tent Campers brochure, 2026.

Mattresses in 54 × 80 in

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Custom size
Mattress Insider Park Meadow Encased Coil II

Mattress InsiderPark Meadow Encased Coil II

  • Hybrid
  • 8 in thick
  • cushion-firm

Sleep Foundation: Best Mattress for Pressure Relief Read review

Made to 54 × 80 inGet a quote
Bedroom in a Flagstaff

The Flagstaff bedroom. Measure the platform, not the old mattress, before you buy.

The 12ST floorplan

Forest River Flagstaff 12ST floorplan, 2026

Forest River's 2026 12ST floorplan.

Is this your 12ST?

Check the year and length against your RV before you order.

YearModelLengthSleeps
2026Flagstaff Hardside T12ST18' 4"–

Other Flagstaff mattress sizes

10LE10RB12FD12RG21HS21HSBAll Flagstaff floorplans

Sources

  1. recreationalvehicles.info: https://recreationalvehicles.info/2026-forest-river-flagstaff-tent-campers/2026-forest-river-flagstaff-tent-campers-brochure-page-002.jpg
  2. recreationalvehicles.info: https://recreationalvehicles.info/2026-forest-river-flagstaff-tent-campers/2026-forest-river-flagstaff-tent-campers-brochure-page-007.jpg

Questions

What size mattress is in the Forest River Flagstaff 12ST?

The main bed is 54 × 80 in (2026 Forest River Flagstaff Tent Campers brochure, 2026).