Water flosser · Waterpik · price guide
Waterpik WP-660 value
A Waterpik WP-660 water flosser sells for about $40.50 on eBay, from 54 sales between Sep 25, 2026 and Oct 26, 2026. Most sell for $34.99 to $49.98. Used ones bring $39.96, new ones $46.66. At local online auctions it has gone for $8.51.
1 sale above $80 drawn at the top edge.
See the numbers
| Month | Sales | Middle price |
|---|---|---|
| Sep 2026 | 3 | $42 |
| Oct 2026 | 51 | $40.49 |
The flip math
What one Waterpik WP-660 is worth to a reseller, line by line.
To keep at least 2 times what you pay, bid no more than $7.74. Above $17.03 you lose money after every fee. Run your own numbers.
Local auction prices
2 single Waterpik WP-660 lots closed at Kansas and Missouri online auctions we track, at a middle winning bid of $8.51.
| Closed | Winning bid |
|---|---|
| Oct 30, 2026 | $8.01 |
| Oct 30, 2026 | $9.01 |
Selling notes
- 33% of sales shipped free; the rest charged a middle $9.59 for shipping.
- 19% sold through Best Offer, where the real price can be lower than shown.
- 41 sold in the last 30 days, 54 in the last 90.
Questions
How much is a used Waterpik WP-660 water flosser worth?
About $39.96 on eBay, the middle of 30 used sales between Sep 25, 2026 and Oct 26, 2026. Most used ones sell for $34.99 to $49.98 once new ones are counted too.
What does a new Waterpik WP-660 water flosser sell for?
New ones sold for a middle price of $46.66 across 24 eBay sales.
How fast does a Waterpik WP-660 sell?
41 sold on eBay in the last 30 days and 54 in the last 90. 33% of sales came with free shipping.
What does a Waterpik WP-660 go for at auction?
At the Kansas and Missouri online auctions we track, 2 single Waterpik WP-660 lots closed at a middle winning bid of $8.51, against $40.50 on eBay.
Is a Waterpik WP-660 worth flipping?
Sold at $34.99 on eBay you keep about $23.90 after fees, shipping and a returns buffer. To double your money, pay no more than $7.74 as a winning bid with an 18% premium and 9% tax.
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Have one? Look it up
Snap a photo or scan the barcode and see what yours sells for, new and used, with every fee counted.
Look up yoursHow we got these numbers
- 54 eBay sales of the Waterpik WP-660 from Sep 25, 2026 to Oct 26, 2026, each one checked to be this model (at least half name it in the listing; the rest match it closely).
- eBay prices are completed sales (what buyers paid), not asking prices, from our sold-data provider. We keep only sales of the same product: parts, accessories, bundles and look-alikes are dropped before anything is counted.
- Local auction prices are winning bids on single-item lots at the Kansas and Missouri online auctions we track (HiBid and Equip-Bid sellers), read by our own lot reader. Lots of several units are left out.
- The money math uses our standard costs: 18% buyer's premium, 9% sales tax, a $2.00 lot fee, eBay's 13.6% + $0.40 fee, shipping at cost (never counted as profit) and a 15% buffer for returns and duds. Members set their own.