When Costco or Sam’s Club is cheaper than Amazon (and when it isn’t)

Start with the unit price, not the sticker

The only fair comparison is price per unit: per ounce, per sheet, per load, per count. Divide the total price by the number of units. Do it for both stores, using the same unit.

• Match the unit. “Count” can mean rolls on one listing and sheets on another. Convert both to the smallest unit you actually use.
• Use the price you will pay. Include shipping, delivery fees and any coupon that applies to your cart. Leave out tax only if it is the same at both stores.
• Read the small print on Amazon. Many Amazon listings show a per-unit price in small type next to the main price, such as a price per count. Check what that count is before you trust it.
• Check the size, not the name. The same brand can come in different pack sizes at different stores, so compare units, not product names.

For Amazon, don’t rely on a price you remember. Use the “Price History” link on the Amazon product page, which Amazon says shows up to 365 days of pricing on many products. That tells you whether today’s Amazon price is normal before you compare it with the club.

Add the membership fee before you call it a win

A warehouse club price is only cheaper if the savings cover the membership. These are the US list prices on the official pages as of September 2026.

Sam’s Club sometimes runs first-year discounts for new members, and its join page listed one as of September 2026. Those change often, so check the page before you sign up.

A simple test: add up what you would really buy at the club in a year, then subtract what the same items would cost elsewhere. If the difference is smaller than the fee, the membership is not saving you money. Both clubs say they will refund your current membership fee if you are unhappy, so a trial year is lower risk than it looks.

Executive and Plus: when the upgrade pays for itself

Costco Executive costs $65 more than Gold Star. It pays a 2% Reward on qualified Costco, Costco.com and Costco Travel purchases, capped at $1,250 a year. 2% of $3,250 is $65, so you need roughly $3,250 a year of qualifying spending just to break even on the upgrade. Some things don’t count, including gasoline, tobacco, Costco Shop Cards, postage stamps, membership fees, cellphones and food court purchases. Costco issues the Reward about three months before your renewal date, so it is not instant money.

Sam’s Club Plus costs $60 more than Club. It pays 2% Sam’s Cash on qualifying pre-tax purchases made in clubs and through Curbside Pickup, capped at $750 per 12-month membership period. The 2% applies to purchases made directly from Sam’s Club in clubs and through Curbside Pickup, not to third-party purchases, so orders shipped to your home are not on that list. On the rewards alone, you need about $3,000 a year of in-club spending to cover the extra $60. Plus also adds free shipping on eligible online orders of $50 or more pre-tax (otherwise an $8 flat fee) and free delivery from the club on eligible orders of $50 or more. Club members pay a $12 delivery fee per order.

If your spending is under those break-even lines and you don’t use the extra perks, the basic tier is the cheaper plan.

Bulk only wins if you use all of it

The lowest unit price is worthless if a third of the pack goes stale, expires or sits in the garage for two years. Before buying big, ask:

• Will I finish it before it expires or goes stale?
• Do I have room to store it without buying something else to hold it?
• Is this a product I already buy, or am I buying it because the pack looks like a deal?
• Would a smaller size at a slightly higher unit price cost less in total, once waste is counted?

Non-perishables you use every week, like trash bags, laundry detergent, paper goods and pantry staples, are where bulk has the best shot. Fresh food, spices you use twice a year and anything with a short shelf life are where bulk most easily costs you money. If you are stocking a kitchen or restocking home basics, run the unit math on the items you go through fastest first.

Kirkland Signature and Member’s Mark

Kirkland Signature is Costco’s own brand. Member’s Mark is the Sam’s Club brand, sold only at Sam’s Club. Store brands can make a club’s unit price look strong, but you are no longer comparing the same product.

That is the catch. A store brand and a name brand are not automatically equal. Compare the parts that matter to you: size, ingredients or materials, and how much you use per load, meal or wash. A cheaper detergent that needs a bigger dose is not cheaper per load.

Amazon has its own brands too, such as Amazon Basics. The same rule applies there: compare the product you would actually be happy using, at the same unit.

Where Amazon can win: Subscribe & Save and shipping

Subscribe & Save. On eligible items, Amazon says you can save up to 15% when you receive 5 or more products in one auto-delivery to one address, and shipping on subscriptions is free. You can skip or cancel at any time. The catch is in Amazon’s own terms: the item price can go up or down between deliveries, and you pay the price on the day the order is processed, minus the discount. Amazon emails a reminder before each delivery with the price, so check that email instead of assuming the first price holds.

Shipping. Prime includes free delivery on eligible items with no minimum purchase. Without Prime, Amazon ships orders free once they include its stated minimum of eligible items. Items from sellers that ship their own inventory can still carry shipping fees. On the club side, each Costco.com product has its own shipping fee (many ship at no extra charge), and Costco says online prices can differ from warehouse prices because of shipping costs and warehouse-only promotions.

So a Costco.com price is not the same as the warehouse shelf price, and Costco doesn’t price-match its warehouse prices for Costco.com orders. Compare like with like: delivered price against delivered price, or shelf price against the cost of driving there.

As an Amazon Associate, SlickRish earns from qualifying purchases made through its Amazon links. That never changes what you pay. Details are on the disclosure page.

Returns: the quiet tiebreaker

Return rules can matter more than a small price gap, especially on bigger items.

• Costco guarantees satisfaction on most products, with exceptions. For TVs, projectors, major appliances, computers, tablets, smart wearable devices, cameras, drones and cell phones, the window is 90 days from when you received the item.
• Amazon takes most items back within 30 days of delivery in original or unused condition. Some categories are shorter, such as new Apple products at 15 days, and some items are non-returnable. If a third-party seller ships the item itself, the return goes back to that seller instead of Amazon.

Check the specific item’s return terms before you buy. On Amazon, the product page shows return eligibility.

A simple checklist before you buy

1. Work out the unit price at each store, in the same unit.
2. Use the delivered price: add shipping or delivery fees, and subtract coupons that actually apply.
3. On Amazon, open the product page’s Price History link to see whether today’s price is normal.
4. Ask whether you will use the whole pack before it expires.
5. If you are comparing a store brand, compare what matters: size, dose and quality.
6. Count your membership fee, and only count Executive or Plus rewards if your spending clears the break-even line.
7. Check the return window for that exact item.
8. If a cashback portal pays on that store, start there. My Rakuten and Capital One Shopping links on this site are referral links, so I may earn a bonus if you sign up. The order I stack things in is in how to stack savings.

If a “was” price looks too good, here is how to tell a real discount from a fake one. Every Top 10 pick on SlickRish has to pass the same checks, written down in how I pick deals. You can browse current Costco and Amazon deals, or get the daily deals by email.