Independent supplement ratingsUS and Canada · Updated weekly
A ratings desk for a category that has spent thirty years grading its own homework.
A ratings desk for a category that has spent thirty years grading its own homework.
Price per serving, anchored list prices and the subscription trap: how to check whether a supplement sale is really a sale before you hand over a card.
Supplements go on sale constantly, and "50% off" is one of the least informative sentences in retail. It tells you the relationship between two numbers the seller chose. Here is how to find out whether you are actually saving anything — in about ninety seconds, without trusting anyone's countdown timer.
This is the single most useful habit in the category, and it defeats most discount theatre on its own. A "40% off" 60-serving tub can easily cost more per serving than a full-price 120-serving tub of the same thing. Take the checkout price, divide by servings — not capsules, not grams, servings as defined on the panel — and compare that number to the alternative you would otherwise buy.
Do this before you look at the percentage, and the percentage stops mattering.
A crossed-out price is a claim about what the seller says the product normally costs. It is not necessarily a price anyone has ever paid. The classic version is a list price set high specifically so that the "sale" price can be the real, permanent price wearing a sticker.
Two checks that take seconds: look up the same product at a second retailer, and look at whether the "sale" price is the same one that was running last month. If a product is on sale every single week, its sale price is its price.
"Subscribe & Save 20%" is often a genuine discount and often the best price available — but read what you are agreeing to. The three things worth knowing before you click: what it renews at (some subscriptions renew at full list price, not the discounted one), how often it ships, and how you cancel.
The version that is not a discount at all is the one where the first box is cheap, the cancellation is a phone call, and the second charge is the real price. That is a different animal, and we have written about how it is built. How the free-trial funnel works →
The deepest discounts often sit on the version a brand is trying to clear — an old formula, a discontinued flavour, or stock near its best-before date. None of those are scandals. But if you are buying because you compared a review to a label, check that the label on the discounted item is the label you compared. Serving sizes and doses change quietly.
The uncomfortable one. A heavily discounted product that is underdosed is not a bargain; it is a cheaper way to buy nothing. Half price on a product whose active ingredient sits at a fifth of the studied dose still leaves you paying for a fifth of a dose.
This is where our rankings are actually useful during a sale: work out what is worth buying first, then look for it on discount — not the other way round. Check a product's dose against the research →
Nearly every misleading supplement discount is one of these four.
The permanent sale. A price that has been "50% off" every week for a year. The list price exists only to be crossed out. Tell: the countdown timer resets when you reload the page.
The bigger tub that costs more per serving. Value sizes are usually cheaper per serving — usually, not always, and the exceptions cluster around sale periods. Always divide.
The subscription anchor. The headline price applies only to the subscribe option, with the one-time price in smaller grey type below it. Not dishonest, but built so you don't compare.
The free gift you paid for. A shaker, a sample, a second tub of something you didn't want, at a price that quietly covers them. Work out the price of the thing you actually came for.
Buying deep on a real discount makes sense for the boring, stable, single-ingredient products — creatine monohydrate, magnesium, plain protein powder. They keep, you will keep using them, and the price rarely drops much further.
Be more careful with anything you have not tried, anything with a short shelf life, and anything in a category where you might change your mind once you read the label properly. A year's supply of something you stop taking in March is the most expensive discount there is.
Check the best-before date before committing to a big pack. Deep discounts sometimes exist precisely because that date is close.
Every price in our rankings is checked at publication and re-checked monthly, and it is price per serving rather than the shelf price. A promotion does not move a score — a ranking that reshuffled itself every time a brand ran a sale would tell you nothing durable. A permanent price change does move it. The full method is here.
Written by the NFS editorial team · Last updated 06 Aug 2026. Some links on this site are affiliate links; they never affect our scoring or the order of any ranking. Advertising disclosure →