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Water Storage Tanks · Size Guide

300 Gallon Water Tank

Complete guide: exact dimensions, full weight, material options, and the best 300-gallon tanks available in 2025.

2,504 lbsWeight When Full
1,136 LVolume in Liters
$240–$520Typical Price Range
40.1 ft³Cubic Feet
⚡ Quick Facts — 300 Gallon Water Tank
Capacity300 US gallons / 1,136 liters / 40.1 cubic feet
Weight Empty55–80 lbs (poly) · varies by material and brand
Weight Full~2,504 lbs (water only) · ~2584 lbs total loaded
Typical Dimensions (Vertical)48" dia × 52" H (Norwesco standard)
Typical Price Range$240–$520 (poly)
Common MaterialsPolyethylene (HDPE), Fiberglass, Galvanized steel
Common UsesFarm water backup, commercial pressure washing, emergency supply
Potable Water Rated?Yes — when specifically labeled for potable use (HDPE tanks)

Who Needs a 300 Gallon Water Tank?

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  • Family emergency backup: Covers a family of four at realistic 3 gal/person/day usage for 25 days — a solid 30-day buffer with slight conservation.
  • Commercial pressure washing: Full-day supply for contractors running a 5–6 GPM washer at a site without water access.
  • Livestock: Weekly supply for a small cow/horse operation or a larger flock of goats or sheep.
  • Irrigation staging: A practical buffer tank for small drip irrigation systems where direct water pressure is inconsistent.
ℹ️
300-gallon is occasionally harder to find in stock than 250 or 500 gallon. If you're between sizes, the 500-gallon is typically better value per gallon and more widely available.

Dimensions by Style

StyleDiameter / WidthHeight / LengthBest UseBrand
Vertical Round48" dia52" HStationary storageNorwesco, Snyder
Horizontal Transport48" dia72" longTruck bed, trailerNorwesco, Chem-Tainer
Leg Tank48" dia52" H + legsElevated gravity feedNorwesco
Dimensions are approximate. Confirm with manufacturer spec sheet before ordering.

Material Options

Polyethylene (HDPE) — Best for Most Uses

High-density polyethylene is the right material for 300-gallon water storage in most applications. It's rotationally molded (seamless), UV-stabilized in black versions, and FDA-approved for potable water storage when labeled. Norwesco and Snyder are the two dominant US manufacturers — both use virgin resin and offer potable-rated versions.

Poly Pros
  • Seamless — no welds or seams to fail
  • Lightweight relative to capacity
  • FDA-approved for potable water (when labeled)
  • No rust or corrosion
  • Best cost-to-capacity ratio
  • 20–30 year lifespan with proper care
Poly Cons
  • Degrades with prolonged UV exposure (use black UV-stabilized tanks outdoors)
  • Not suitable for fuels, solvents, or chemicals
  • Requires freight delivery at this size
  • Large tanks need equipment to unload

Corrugated Steel

At 300 gallons, corrugated steel tanks exist but poly is typically better value unless you specifically need the durability of steel or a panel-assembled configuration for your site. Steel requires a food-grade liner for potable water and the liner needs replacement every 10–20 years. For pure water storage, poly is the better choice at this size.

Top 300 Gallon Water Tank Picks (2025)

Best Overall
🛢️
Norwesco 300 Gal Vertical Poly Tank
300 gal · 48"Ø × 52"H · 2" fitting · ~65 lbs empty · Potable-rated
~$339–$419
Check Price at Tank Depot →
Best Value
🛢️
Snyder Industries 300 Gal Vertical
300 gal · 48"Ø × 50"H · 1.5" fitting · ~60 lbs empty · UV-stabilized
~$309–$389
Check Price on Amazon →
Best for Transport
🚛
Norwesco 300 Gal Horizontal Transport Tank
300 gal · 48"Ø × 72"L · Flat-bottom transport · 2" outlet
~$369–$449
Check Price at Tank Depot →

Where to Buy a 300 Gallon Water Tank

RetailerTypical PriceShippingNotes
Tank Depot~$339–$419Freight deliveryBest selection; multiple styles and fittings options
Amazon~$309–$389Freight for this sizeCompetitive pricing; check seller ratings carefully
Tractor Supply Co.VariesIn-store or deliveryStocks smaller sizes; call ahead for 300 gal availability
Local Farm Supply / Co-opVariesLocal pickupOften cheapest; limited to standard configurations
This size ships freight — confirm delivery access and unloading equipment before ordering.

Installation Notes

At 2,504 lbs when full, proper installation matters. Key considerations:

  • Foundation: Flat, level, compacted surface. Concrete pad strongly recommended for permanent installations. Compacted gravel is acceptable for lighter use.
  • Delivery: This size ships via freight flatbed. You'll need a tractor with front loader, forklift, or pallet jack to move the tank off the truck. Coordinate equipment before the delivery date.
  • Plumbing: Standard outlet is 48" NPT. Budget for a ball valve, 50 mesh strainer, and appropriate hose fittings.
  • Permits: Usually not required for residential aboveground tanks under 5,000 gallons. Check with your county if the tank connects to a potable plumbing system.
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Frequently Asked Questions

A standard vertical round 300-gallon poly tank (Norwesco) measures approximately 48 inches in diameter and 52 inches tall for a standard vertical poly tank. At this size the tank ships via freight — confirm delivery access before ordering..

Water weighs 8.345 pounds per gallon. A full 300-gallon tank contains approximately 2,504 pounds of water. Add the tank's empty weight (55–80 lbs for poly) for a total loaded weight of roughly 2584 lbs.

Standard poly 300-gallon tanks cost $240–$520 depending on brand and retailer. Norwesco runs ~$339–$419; Snyder is slightly cheaper at ~$309–$389. Freight delivery adds $75–$200 depending on your location. Fiberglass alternatives start significantly higher.

Yes, provided the tank is specifically rated for potable water. Look for tanks labeled "FDA-approved," "NSF/ANSI 61," or "safe for drinking water." Both Norwesco and Snyder offer potable-rated 300-gallon tanks. Never use a tank previously used for chemicals, even if cleaned.

A quality Norwesco or Snyder tank carries a 3-year warranty but realistically lasts 20–30 years with proper care. Use black UV-stabilized tanks outdoors, don't store empty in freezing temperatures, and inspect outlet fittings annually for stress cracks.

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