TL;DR — We priced twelve floss spools and refills and six reusable holders at named US retailers on one day and divided every pack price by the meters in the pack. The cheapest confirmed floss is store-brand nylon at $0.0199 per meter; the most expensive is a refillable-format spool at $0.3304 per meter — a 16.6× spread for the same daily job. The cheapest floss marketed as plastic-free lands at $0.0465 per meter, which undercuts every branded nylon row we could confirm. Annualized at one 18-inch use a day, the whole market runs from $3.32 to $55.14 a year.
All prices in this article were read at the named US retailers on 31 August 2026 and change without notice.
Per-pack prices hide the number that matters. A $1.00 spool and a $9.97 spool look ten times apart; per meter they are sixteen times apart, because the packs hold different lengths. This article does one thing: it divides every confirmed pack price by the meters in the pack, then annualizes on a single stated assumption — extending our braces-tools survey from 23 August with the ordinary-floss aisle it deliberately left out.
Method
Prices were read at Walmart.com, Target.com, Walgreens.com, Amazon.com and six brand-direct sites (better-objects.com, dentallace.com, getquip.com, thegoodfill.co, ecoroots.us and sunstargum.com) on 31 August 2026, directly on each product page. This survey prices what floss costs; it makes no claims about how any product performs, and where a listing says "silk" or "bamboo," that is the manufacturer's description of its own product, not something we tested.
- Confirmed prices only. Every row below had its price verbatim in the fetched page content. Three spool rows failed that check on re-verification and are excluded entirely — they are listed in "What we could not price," without their prices.
- List price, not member price. Where a page showed a public sale price (three rows did), we recorded the current public price and note it.
- Yards converted at 1 yd = 0.9144 m. Per-meter price = pack price ÷ total meters in the pack, computed deterministically from the recorded numbers, not re-derived by hand.
- Annualizing: the American Dental Association's floss guidance page describes cleaning between teeth once a day, and 18 inches (45.72 cm) is the length its guidance describes per session. We annualize on that basis: 365 × 0.4572 m = 166.9 m of floss a year. Cost per year = price per meter × 166.9. If you use less, every yearly figure below shrinks proportionally; the ranking barely moves.
- Spot-check: the three most expensive rows per category plus one random row were re-fetched the same day. Rows whose price could not be re-found in page content were dropped.
Price per meter, and what a year costs
At 166.9 m a year, a standard 55-yard (50.29 m) spool lasts about 110 days — call it 3.3 spools a year. Here is every confirmed row, cheapest first. "Cost per year" is price per meter × 166.9 m, the assumption stated above.
Figure 1 — Price per meter, confirmed floss routes
| Product | Retailer (31 Aug 2026) | Pack price | Meters in pack | Per meter | Cost per year |
|---|---|---|---|---|---|
| Equate Mint Waxed Nylon Floss, 55 yd | Walmart.com | $1.00 | 50.29 | $0.0199 | $3.32 |
| The Humble Co. Floss, 4 × 55 yd | Walmart.com | $9.35* | 201.17 | $0.0465 | $7.76 |
| up&up Mint Floss, 2 × 54 yd | Target.com | $5.79 | 98.76 | $0.0586 | $9.78 |
| Oral-B Satin Floss, 2 × 54.6 yd | Walgreens.com | $6.79 | 99.85 | $0.0680 | $11.35 |
| Oral-B Glide Deep Clean, 3 × 40 m | Amazon.com | $9.97 | 120.00 | $0.0831 | $13.87 |
| Oral-B Glide Deep Clean, 3 × 40 m | Target.com | $9.99 | 120.00 | $0.0833 | $13.90 |
| REACH Mint Waxed Floss, 55 yd | Walmart.com | $5.40* | 50.29 | $0.1074 | $17.93 |
| The Good Floss silk refill + steel dispenser, 2 × 33 yd | thegoodfill.co | $7.50 | 60.40 | $0.1242 | $20.73 |
| Oral-B Glide Deep Clean, 43.7 yd | Walgreens.com | $5.00* | 39.96 | $0.1251 | $20.88 |
| TreeBird Pure Silk refill spools, 2 × 33 yd | Amazon.com | $9.99 | 60.35 | $0.1655 | $27.62 |
| EcoRoots Zero Waste Floss, glass jar + 3 × 30 m bamboo rolls | ecoroots.us | $14.97 | 90.00 | $0.1663 | $27.76 |
| Cocofloss refillable spool, 33 yd | Walmart.com | $9.97 | 30.18 | $0.3304 | $55.14 |
\Public sale price on the day: Humble Co. was listed at $10.39, REACH at $6.82, and the Walgreens Glide at $5.79 before the shown price. The Good Fill, EcoRoots and Cocofloss rows include a dispenser or container in the price, which inflates their per-meter figure on the first purchase; EcoRoots showed an "Unavailable" button with the price still displayed.*
Three readings of that table, arithmetic open:
The full spread is 16.6×. $0.3304 ÷ $0.0199 = 16.6. At one use a day that is $3.32 against $55.14 a year — a $51.82 gap for pulling a string between your teeth.
Format costs more than fiber. The cheapest floss marketed as plastic-free — The Humble Co. at $0.0465 per meter (Walmart.com, 31 August 2026) — is cheaper than every branded nylon row we confirmed: both Oral-B Glide 3-packs ($0.0831–$0.0833), the Oral-B Satin 2-pack ($0.0680) and the REACH single spool ($0.1074). Only the $1.00 store-brand spool beats it. What is expensive is not the eco fiber; it is small packs and bundled containers. The same Oral-B Glide floss costs $0.0831 per meter in a 3-pack and $0.1251 per meter as a single 43.7-yard spool at Walgreens — a 51% premium for buying one at a time.
The dearest row is a refillable-format product. The Cocofloss 33-yard spool tops the table at $0.3304 per meter. Its Walmart listing calls it "refillable"; its fiber composition is not on the price page, and we did not test it, so it sits in this survey as a format example, not a materials claim. The silk-marketed refills (TreeBird, The Good Fill) cluster at $0.12–$0.17 per meter — a 2.7–3.6× premium over Humble Co., which is where the real plastic-free price decision lives. What those fibers are actually made of is its own article; why anyone pays the premium at all is partly a microplastics question.
What we could not price
- CVS.com is geo-blocked outside the United States and contributed nothing to this survey.
- Three spool rows were dropped at verification: a Reach 200-yard refill 2-pack and a TreeBird 5 × 33 yd refill pack on Amazon (prices render dynamically and could not be re-found in page content — the Reach price was additionally a third-party offer), and a Reach 55-yard spool at Walgreens, where the server answered 403 on re-check. Their prices are not cited here.
- Georganics floss refills had no Amazon offers at all on the day.
- The holder category is nearly invisible at big-box retail: Walmart's holder search sat behind a CAPTCHA wall, Target's quip starter-kit page 404'd, and Amazon's holder pages rendered without a citable price — which is why every one of the six holder prices comes from a brand-direct site, where list prices are typically at their most flattering.
- The Good Fill's $7.50 may be the refill-only variant rather than the dispenser bundle; the page did not disambiguate, so its per-meter figure carries that uncertainty.
What would change this
A restock or price move on any of the three sale-priced rows shifts the middle of the table; a confirmed price on the Reach 200-yard refill would very likely become the cheapest refill-format row and deserves a re-check from a US IP; and if the ADA's once-a-day framing is not how you actually live, every yearly figure scales linearly with your own frequency. We re-run this survey quarterly and date-stamp every number.
Disclosure: this article is published by LastObject, which is taking pre-orders for the LastFloss holder priced above. The survey's price table contains no LastObject floss, our product appears only with its pre-order caveat spelled out, and the cheapest way to floss in this article remains a $1.00 spool of nylon from Walmart.
