Easy Stock Buffer - Shopify safety stock

Stop overselling. Keep a safety stock buffer.

A two-hour flash sale sells 40 of a shirt you had 32 of. Monday morning is eight refund emails and an apology.

Easy Stock Buffer lets you set a floor, say 5 units, and Shopify stops taking orders for that variant once stock reaches it. The check runs at checkout, so a Shop Pay tap cannot slip past it.

Free planNo code to writeHolds on Shop PayTwo steps to switch on

Install on Shopify See how it works

5.0 on the Shopify App Store, from 1 review. Checked July 22, 2026.

Linen Shirt - Sand / M

SKU LIN-SND-M

Buffer active

In stock32

Your floor: 275 free to sell

What the shopper sees

Only 5 of "Linen Shirt" can be ordered right now.

How it works

Three things to do, then it runs on its own

Pick a number for each product

Set a floor on the variants you care about, or one default for the whole shop. Most people use roughly what they sell while a restock is in transit. Your Shopify inventory count is left alone.

Switch the checkout rule on

Shopify does not turn an app checkout rule on by itself. There is a button in the app that does it, or you add it by hand under Settings > Checkout > Checkout rules. About 30 seconds, once.

Shopify stops the order at checkout

After that, any order that would take stock below your floor is stopped at checkout with a message you wrote. The cart stays open, so a shopper can drop the quantity and finish the rest of their order.

Eight stock units in a row: the first three shaded pink and bracketed as available to buy, the remaining five shaded teal and bracketed as the protected safety-stock buffer that blocks checkout — Nothing here writes to Shopify. The app reads your stock count and the floor decides how much of it the store is allowed to sell.

Flow showing a shopper adding to cart with the cart left open, then checkout starting however they pay, then the stock floor check running inside Shopify, which either lets the order through when stock stays above the buffer or blocks it with your own message when the order would take stock below it — We leave the cart alone on purpose. Block it there and Shopify shows its own unbranded error page. At checkout, your wording is what the shopper reads.

Safety stock vs order limits

A different job from an order-limit app

Order-limit apps cap how many units one customer can buy, which is handy against resellers and does nothing about overselling. Easy Stock Buffer works the other way round: once stock reaches your floor, the variant stops selling to everybody. Shopify has no built-in setting for that.

How an order-limit app compares with Easy Stock Buffer's safety-stock floor.
Feature	Order-limit appsCap units per customer	This appEasy Stock BufferSafety-stock floor
Caps how many units one customer can buy	Yes	No
Stops selling to everyone once stock hits your floor	No	Yes
Leaves a buffer for returns, damages and miscounts	No	Yes
Where the rule is enforcedCheckout is the only point every payment path goes through	Varies by app	Shopify checkout
Built for	Resellers, wholesale minimums	Never overselling

Features

What else is in there

It holds on Shop Pay

The check runs inside Shopify at checkout instead of as a script in your theme, so express wallets and pasted checkout links go through it too.

One number, or one per product

A floor per variant, with a shop-wide default underneath for everything else. On Pro you can set them in bulk, by collection, tag or product type.

A floor per location

On Pro, your warehouse and your shop floor each hold back their own reserve. The app adds them up into the single number Shopify checks at checkout.

An email before you get there

Ten alerts a month on the free plan, unlimited on Pro. On Pro you can also roll them into a daily or weekly digest instead of one email per product.

Sold-out products go to draft

On Pro, a product that runs out moves to draft on its own and returns to its old status when stock comes back. You can point the old URL somewhere useful in the meantime.

A suggested number to start from

On Pro, the app watches how fast each variant has been moving and proposes a floor. It wants at least three sales in the window before it will guess.

Four stacked levels showing which stock threshold wins: a variant-level threshold first, then a bulk rule for a collection, tag or product type, then the shop-wide default, and finally no threshold at all — Set one number shop-wide, then override it per collection or per variant. The most specific rule wins, and a variant with nothing set falls through to the default.

Pricing

Free for 10 products, $7 for the whole catalogue

The free plan is a real plan, not a trial. Ten variants get their own floor, and one shop-wide default covers every other variant in the store.

Free

$0/month

For your first few products.

Ten variants with their own floor
One shop-wide default for everything else
Blocking at checkout, every payment path
Blocks Add to cart at your floor
10 stock alerts a month

Easy Stock Buffer FAQ

What merchants ask before adding a safety-stock buffer to their Shopify store.

How long does Easy Stock Buffer take to set up?

About five minutes, and two things have to happen. You set a floor on at least one product, then you switch on the app’s checkout rule - one button in the app, or by hand under Settings > Checkout. Floors save fine before that, but nothing is enforced until the rule is on.

Does it change my Shopify inventory numbers?

No. The app reads your stock and never writes to it, so your inventory counts and your reports read exactly as they did before. The floor is a separate number it compares your stock against at checkout.

What does a shopper see when an order is blocked?

A message on the checkout page, in your wording. Out of the box a partly blocked line reads "Only 5 of Linen Shirt can be ordered right now", and a fully blocked one says the item is held in reserve. The cart stays open, so they can lower the quantity and check out with the rest.

Does it work with Shop Pay and express checkout buttons?

Yes. The check runs inside Shopify at checkout rather than as a script in your theme, so every one-tap wallet and pasted checkout link passes through it. There is one gap worth knowing about - a headless or Hydrogen storefront can add an over-floor line to a cart, and that order still gets stopped at checkout.

Do I have to edit my theme?

Not for the checkout block, which lives entirely in the app. If you want shoppers stopped earlier, the app has a theme embed that greys out Add to cart and blocks the Check out button in the cart. You switch it on in your theme editor - a toggle, not code.

What happens to my store if I uninstall?

Blocking stops straight away, because the checkout rule runs on the app’s own function. Your floors and settings sit untouched for 48 hours in case you reinstall, then they are deleted. Check one thing before you go, though - if auto-hide moved products to draft, they stay in draft.

What does the free plan actually cover?

The free plan does the same blocking as Pro, capped at ten variants with a floor of their own. One shop-wide default still covers every other variant in the store. Pro is $7 a month with a 7-day trial and removes the cap.

Can I set different floors for different products?

Yes. Set a number per variant, with a shop-wide default underneath for everything you have not touched, and the most specific rule wins. On Pro you can also set floors in bulk, or one per location.

Stop selling before you run out

Pick a number, switch on the checkout rule, and your next promotion stops itself at the floor you chose. Start on the free plan and see it block one order before you pay anything.

Install on Shopify

Free plan, no card needed.

Easy Stock Buffer

Free plan on the Shopify App Store

Stops the order at checkout

A floor per variant, or one for the shop

Email alerts before you get there

Holds on Shop Pay

More on keeping stock back

How to prevent overselling on Shopify

Why Shopify lets an order through when the stock is already gone, and the five usual causes.

Working out your safety stock level

Lead time, daily sales rate, and the arithmetic behind the number you end up typing in.

Order limits vs safety stock

Which of the two you actually need, and when a store wants both running together.

What to use when Stocky shuts down

Stocky retires on 31 August 2026. What moves to native Shopify and what does not.

What safety stock means

The definition, both formulas, and how it differs from a reorder point.

Easy Stock Buffer help docs

Setup, thresholds, alerts, and what to check when a product is still selling.