The correct spelling is "sump pump" — two words, lowercase
Sump pump is spelled as two separate words: "sump" and "pump". The word "sump" refers to the pit or basin where water collects in your basement or crawlspace, and "pump" is the device that moves that water out. You will not find it written as "sumppump" or "sump-pump" in technical manuals or manufacturer documentation, though hyphenated versions appear occasionally in older texts.
When you are searching for parts, reading your warranty, or talking to a plumber, use the two-word form. It is the standard across the plumbing industry, home inspection reports, and building codes. If you are writing the term at the start of a sentence, capitalize only the S: "Sump pump installation requires a check valve."
Key Takeaways
- The correct spelling is "sump pump" — two words, not one hyphenated word or compound.
- The word "sump" comes from the basin or pit where groundwater and basement seepage collect.
- Using the correct spelling helps you find accurate product information, parts, and professional help.
- Manufacturers, plumbers, and building codes all use "sump pump" as the standard term.
- Common misspellings like "sumppump" or "sump-pump" may return fewer or less relevant search results.
Why the word "sump" is spelled that way
The word "sump" has been used in English since the 1600s to describe a pit or reservoir where liquid collects. It comes from Dutch and German roots related to swamps and low-lying areas. In plumbing, a sump pit is literally a hole dug below the basement floor where water naturally drains and pools before the pump removes it.
The spelling S-U-M-P has remained consistent across centuries and across different languages. You will see it in old building documents, modern manufacturer spec sheets, and plumbing code books. It is not a technical term invented recently — it is a word with real history in construction and drainage.
Common misspellings and why they happen
People often write "sumppump" (one word) because the two words run together when spoken quickly or when someone is typing from memory. Others write "sump-pump" with a hyphen, treating it like a compound modifier — similar to "water-heater" or "check-valve". Both versions appear in casual writing and even on some older websites, but they are not standard.
Search engines will usually understand what you mean if you type a misspelling, but you may get fewer results or results that include pages using the correct spelling. If you are looking for a specific part number, a warranty document, or technical support, using "sump pump" (two words, no hyphen) will get you to the right information faster.
How to use the term correctly in writing
When "sump pump" appears in the middle of a sentence, both words are lowercase: "The sump pump runs automatically when water rises in the pit." When it starts a sentence, capitalize only the first word: "Sump pump maintenance includes testing the float switch twice a year."
If you are using it as an adjective before another noun, the two words stay separate: "sump pump installation" or "sump pump failure". You do not combine them or add a hyphen. This matches how other plumbing terms are written — "water heater", "check valve", "drain pipe" — each as separate words.
Where you will see the correct spelling used
Manufacturer manuals from brands like Zoeller, Liberty, and Wayne all use "sump pump" as two words on their product pages, installation guides, and warranty documents. Building codes, including the International Residential Code (IRC), refer to it as "sump pump" in sections covering basement drainage and water management.
Plumbing supply catalogs, home inspection reports, and real estate disclosures all use the two-word spelling. If you are reading a document and see a different spelling, it is likely an informal note or an older text — the industry standard has always been "sump pump".
Why spelling matters when you need help
When you call a plumber or visit a supply store, using the correct term helps you communicate clearly. A plumber will know when ready what you are talking about. If you are ordering parts online, searching for "sump pump" will return product listings, replacement parts, and accessories much faster than a misspelled version.
If your sump pump fails and you need to file a warranty claim or look up troubleshooting steps, the manufacturer's website will have documentation filed under "sump pump". Using the correct spelling means you find the right manual for your model without wasting time on search results that do not match what you need.
Frequently Asked Questions
Is it ever correct to write "sump-pump" with a hyphen?
Hyphenated versions appear in some older texts and casual writing, but the standard spelling across the plumbing industry, building codes, and manufacturers is two separate words with no hyphen. Use "sump pump" for any formal writing, product searches, or communication with professionals.
What if I misspell it when searching online?
Search engines are usually forgiving and will show you results for "sump pump" even if you type a misspelling. However, you may get fewer results or results that include pages using the correct spelling. For the fastest and most accurate results, use "sump pump" as two words.
Does the spelling change if I am talking about more than one?
No. The plural is "sump pumps" — you straightforward add an S to the end of "pump". You do not change the spelling of "sump" itself. For example: "The building has two sump pumps in the basement."
Should I capitalize it if it is a brand name?
No. "Sump pump" is a generic term for the device, not a brand. Brand names like "Zoeller" or "Liberty" are capitalized, but the device itself is always "sump pump" in lowercase unless it starts a sentence.