Crest’s most popular at-home whitening strips just reached a can’t-ignore price on Amazon, where the experiential 22-treatment box of Crest Whitestrips Professional Effects has dropped to $29.99 (regularly priced at $42.99), or 30% off and matching its lowest-price pattern during big sales.
For shoppers looking to replenish oral care staples or add a small self-care upgrade to their cart, this deal brings the cost per whitening session to about $1.36, substantially less than most professional treatments will run you per visit.
- Here’s what you need to know about this price-war one-upmanship
- What You Get With Crest Professional Effects Whitestrips
- Safety and Efficacy as Reported by Experts
- How We Compared Whitestrips to Other Whitening Options
- Tips to Get the Most Out of It and Save More
- Bottom line on this at-home whitening deal

Here’s what you need to know about this price-war one-upmanship
Professional Effects simply doesn’t drop below the $30 mark very often, so deal hunters and dental-care hobbyists have a tendency to jump on it when the price is right. It actually mimics the headline Black Friday price without all of the holiday season madness.
There’s also a bonus to keep an eye on: Amazon often carries out a Procter & Gamble household promotion that takes off an extra $5 when you purchase two qualifying products, so you can double up on Whitestrips and stock up on everyday items like toothpaste or floss for more value.
What You Get With Crest Professional Effects Whitestrips
The box comes with 22 treatments (or 44 strips total) for an easy 22-day treatment plan. Each session is around 45 minutes. Its no-slip grip, according to Crest, helps the peroxide gel stay in place so you can talk a little or sip water while the strips are working.
According to Crest testing, there can be up to 19 shades of whitening after completing the full treatment with an enamel-safe formula, which is safe for daily use during the whitening period. Note that real-world results will fluctuate among users, depending on the condition of your enamel, diet, and what type of stains you have. However, little else delivers in quantity (or quality); many users see a visible difference within one week, and some even report full results after two or three.
Safety and Efficacy as Reported by Experts
At-home strips contain low-percentage hydrogen peroxide (or carbamide peroxide) at a concentration of about 3 to 10 percent that is designed for gradual whitening. There is evidence from the Cochrane Collaboration and statements by the American Dental Association that at-home bleaching can be a successful option in some situations compared to placebo, although the most common side effects are tooth sensitivity and transient gingival irritation.
If you’ve had sensitivity in the past, some dentists recommend switching to a toothpaste that has potassium nitrate prior to starting and during whitening; spreading sessions further apart and doing them every other day; and steering away from very hot or cold foods directly after treatment. And anyone with dental restorations, untreated cavities, or active gum disease should see a dentist before using any whitening product—crowns and fillings will not change color.

How We Compared Whitestrips to Other Whitening Options
With adhesive that is pressed up against the tooth and then conforms to the ridges and crevices, “you receive more uniform and even contact with the teeth than from a rinse or a pen,” explains Dr. Dodes.
LED add-ons are very popular online, but independent studies suggest it may be peroxide concentration and wear time that drive results—not the light itself.
In-office whitening as done by a dentist uses higher-percentage peroxides and can whiten teeth several shades over the course of an hour-long visit, but it generally costs a few hundred dollars or more. For many users, a sub-$30 box of strips will provide a good, gradual brightening at a fraction of the cost.
Tips to Get the Most Out of It and Save More
Place strips onto clean, dry teeth; after brushing, blot them with tissue to help them stick. The day of the 45-minute session, and for about an hour afterward, avoid strongly pigmented foods and drinks such as coffee, red wine, soy sauce, and berries in order to minimize re-staining. Keep any additional boxes in a cool, dry location to preserve potency.
To help stretch your budget, look for the P&G multi-item promotion above when it becomes available again, and combine with other items on oral care. If you are building a routine, brushing with a whitening-safe toothpaste and flossing every day in between treatments will help keep the shade changes up so you won’t have to repeat as many times throughout the year.
Bottom line on this at-home whitening deal
At $29.99 for 22 treatments, Crest Whitestrips Professional Effects hits a low price point with its high-performing kit that matches our top pick of the year for similar savings. Inventory and pricing for Amazon products are subject to change, but the deal your teeth have been waiting for in an at-home whitening solution is upon us!