Use the chart below to find your sump pump size by horsepower (HP) and vertical lift height. A typical residential basement with a 10 ft lift needs a 1/3 HP pump delivering ~2,400 GPH; heavy inflow or deeper pits need 1/2 or 3/4 HP. All figures are based on Zoeller and Wayne published performance curves. Use our free calculator for an exact GPH in 60 seconds.
Sump Pump Sizing Table: GPH by Horsepower & Lift Height
Pump HP
5 ft Lift
10 ft Lift Most common
15 ft Lift
20 ft Lift
1/3 HP
3,000 GPH
2,400 GPH
1,800 GPH
1,200 GPH
1/2 HP
3,600 GPH
3,000 GPH
2,400 GPH
1,800 GPH
3/4 HP
4,800 GPH
4,200 GPH
3,600 GPH
2,700 GPH
1 HP
6,000 GPH
5,100 GPH
4,200 GPH
3,300 GPH
How to read: Find your pump’s HP on the left. Pick the column that matches your total vertical lift (discharge height above pump + pipe friction). The cell gives the rated GPH at that lift. Color key: green = sufficient for most residential basements, amber = upgrade for heavy inflow, orange = high-output, red = commercial or specialty. Lift includes pipe friction losses (~1 ft per 10 ft of horizontal discharge pipe).
Adjustments: When to Go Up in HP
Heavy Rain / High Water Table
If your area gets 4+ inches of rain or you have a high water table, go up one HP from the chart recommendation.
Finished Basement
For finished basements with a bathroom or laundry, go up one HP and add a battery backup.
Long Horizontal Discharge
For every 10 ft of horizontal pipe, add ~1 ft of effective lift due to friction losses.
Example: 10 ft vertical lift, 30 ft horizontal pipe (+3 ft friction), finished basement, high water table = 1/3 HP (base) + heavy rain upgrade + finished basement upgrade = 1/2 HP submersible with battery backup.
Sump Pump Comparison: 1/3 HP vs 1/2 HP vs 3/4 HP
Feature
1/3 HP
1/2 HP
3/4 HP
GPH @ 10 ft lift
2,400
3,000
4,200
Typical Power Draw
400–500W
600–800W
800–1,100W
Submersible Noise
50–58 dB
52–60 dB
55–65 dB
Max Lift (TDH)
~22 ft
~26 ft
~30 ft
Submersible Cost
$100–$200
$150–$300
$250–$450
Pedestal Cost
$80–$150
$120–$220
$200–$350
Best For
Normal basements
Deep pits, finished basements
Flood-prone, high water table
Total Dynamic Head (TDH) Explained
Total Dynamic Head (TDH) is the total resistance the pump must overcome — it equals the vertical lift from pump to discharge plus friction losses from horizontal pipe and fittings. A typical residential sump pump installation has 8-12 ft of TDH. Always size for the worst case: if your discharge pipe can be partially blocked by ice, debris, or check-valve failure, add 2-3 ft of margin. Manufacturers publish full performance curves showing GPH at every TDH; use the curve to find your actual operating point.
Vertical lift only
Add the height from the pump inlet to the discharge outlet (where water exits the pipe). Most basements: 6-10 ft.
Friction losses
Add 1 ft per 10 ft of horizontal pipe, plus 1 ft per 90° elbow. Standard 1-1/2" PVC pipe: ~1 ft per 10 ft.
Sump Pump Sizing FAQ
How do I use this sump pump sizes chart?
Find your vertical lift height (pump to discharge outlet) and add 1 ft per 10 ft of horizontal pipe for friction losses. The total is your Total Dynamic Head (TDH). Find the column that matches your TDH, then look down to see what each HP delivers at that lift. Go up one HP for heavy rain areas, finished basements, or high water tables.
What size sump pump for a typical basement?
A typical residential basement with a 10 ft lift needs a 1/3 HP pump delivering ~2,400 GPH. For finished basements or high water tables, go up to 1/2 HP. For flood-prone areas or very deep pits, 3/4 HP. Always add a battery backup if your area has frequent power outages.
What is Total Dynamic Head (TDH)?
Total Dynamic Head is the total resistance the pump must overcome. It equals the vertical lift from pump to discharge outlet, plus friction losses from horizontal pipe (about 1 ft per 10 ft) and fittings (1 ft per 90-degree elbow). Standard residential sump pump installations have 8-12 ft of TDH.
How do I calculate my sump pump's GPH needs?
For most residential basements, the pump needs to clear a typical rain event's inflow. A 1/3 HP pump at 10 ft lift delivers 2,400 GPH — enough for most homes. For flood-prone areas, go up to 1/2 HP (3,000 GPH) or 3/4 HP (4,200 GPH). Always check the manufacturer's performance curve for your specific TDH.
Need an Exact GPH Recommendation?
Our free calculator factors in pit depth, lift height, and seepage level for a custom HP in 60 seconds.
Each pick is matched to its HP and GPH-at-lift range. We verify specs against manufacturer pump curves and sort by value — never by commission. Read our product policy.
Best 1/3 HP Sump Pumps — most basements
WAYNE SPF33-1/3 HP Epoxy Coated Steel and Thermoplastic Submersible Sump Pump - Up to 3,750 Gallons Per Hour - Long Lasting and Durable Construction #ad
WAYNE CDU790-1/3 HP Submersible Cast Iron and Stainless Steel Sump Pump with Integrated Vertical Float Switch - Up to 4,600 Gallons Per Hour - Heavy Duty Basement Sump Pump, Black #ad
Little Giant 6-CIA 115 Volt, 1/3 HP, 2760 GPH Cast Iron Automatic Submersible Sump Pump with Integral Diaphragm Switch for Sump Systems, 10-Ft. Cord, Blue, 506158 #ad
Little Giant 6-CIA 115 Volt, 1/3 HP, 2760 GPH Cast Iron Automatic Submersible Sump Pump with Integral Diaphragm Switch for Sump Systems, 10-Ft. Cord, Blue, 506158 #ad
Acquaer 1/3 HP Automatic Submersible Water Pump, 115V Sump Pump with 3/4” Garden Hose Adapter, 2160 GPH High Flow Water Removal for Swimming Pool Cover Hot Tubs Flooded House Basement, Black #ad
WAYNE - 1/2 HP Sump Pump with Integrated Vertical Float Switch and 12 Volt Battery Back Up Capability, Battery Not Included - Up to 5,100 Gallons Per Hour - Heavy Duty Basement Sump Pump System #ad
AQUASTRONG 1/2 HP Sump Pump, 3450 GPH Stainless Steel and Thermoplastic Submersible Water Pump, Automatic Float Switch with Piggy-back Plug,1-1/2" NPT Discharge Subpumps for Basement and Flooding Area #ad
Westinghouse Sump Pump 1/2 HP 69 GPM Submersible Water Pump Automatic Vertical Float Switch Heavy Duty Basement Crawl Space Flood Removal Pump High Flow Water Drainage #ad
AQUASTRONG 3/4 HP Sump Pump, 4200 GPH Stainless Steel and Thermoplastic Submersible Water Pump, Automatic Float Switch with Piggy-back Plug,1-1/2" NPT Discharge Subpumps for Basement and Flooding Area #ad
Westinghouse 3/4 HP Submersible Cast Iron and Stainless Steel Sump Pump with Integrated Vertical Float Switch - 6,000 Gallons Per Hour - Heavy Duty Basement Sump Pump #ad
FLUENTPOWER Submersible Sump Pump 3/4HP 3500GPH, with Piggy-back Vertical Float Switch and 10' Cord, Portable Electric Cast Aluminum Sump/Sewage Pump for Basement Pool Garden Pond Basin, Black #ad
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