Customers can add unlimited quantities of a limited-stock item to cart on Square Online

[RencArt]

Hi everyone,

I’ve noticed an issue on my Square Online store and wanted to check if others have experienced the same thing.

I have several unique, one-of-a-kind items, each with only 1 available in stock (inventory tracking is enabled in my Square Dashboard). However, on the product page, customers are still able to increase the quantity in their cart beyond the available stock for example, they can add 2, 3, or more of an item even though I only have 1 in inventory.

When they reach checkout, Square does show a warning saying that the quantity exceeds available inventory (“has exceeded available inventory, please adjust quantity to continue checkout”), and they can’t complete the purchase so the stock control technically works, but the problem is that customers can still add multiple units to the cart before that.

Here’s what I’ve already checked:

• ✅ Inventory tracking is enabled for the item (quantity set to 1).

• ✅ “Track inventory in Square” is turned on in the Online settings.

• ⚠️ Issue persists across browsers and devices.

I’d like to know if there’s a way to:

1. Prevent customers from adding more than the available quantity directly on the product page (e.g., disable the “+” button once the limit is reached), or

2. Confirm if this is expected behavior in Square Online and only enforced at checkout.

Any insights, best practices, or workarounds (custom code, app integration, etc.) would be greatly appreciated!

Thanks in advance

[Stacelyn24 · Accepted solution]

Hey there! 👋 Great question — and you're absolutely on point in your observations.

You’re right: Square Online currently enforces inventory limits at checkout, not at the product page level. That’s why customers can keep clicking the “+” button and add more than what’s actually in stock — but they get stopped when they try to check out.

🔍 Here's Why That Happens:

Square’s logic allows shoppers to add as many items as they’d like to their cart, but the system only validates the actual inventory at the point of checkout. This is especially helpful when inventory changes fast (like in cafes or venues), but it's not ideal for one-of-a-kind or limited-stock items like yours.

🛠️ What Can You Do (Right Now)?

While there's no built-in setting to cap cart quantity on the product page, here are some workarounds:

1. Use Item Variants (even if you only have 1)
   Even setting something like “Original – 1 available” may visually remind buyers there's only one in stock.

2. Add a Custom Note
   In your item description, add a note like:
   🔹 “Only one available — the cart will only allow checkout for 1.”

3. Add Custom Code (Advanced)
   If you’re comfortable with HTML/JavaScript and you're using a more customized theme, you can use injected code to disable the "+" button after 1 is added. It’s not officially supported by Square, but it has worked for some sellers.

4. Submit Feedback
   Since this is a real usability issue for sellers with exclusive inventory, I highly recommend sending this to Square’s product team via Dashboard > Settings > Feedback. The more voices, the better!

✅ TL;DR:

This is expected behavior with Square Online right now — the inventory limit is enforced at checkout. If you depend on strict, visible limits (like for art, antiques, or handmade one-offs), the workarounds above are your best options for now.

Hope that helps!

[rhysmith]

I've noticed this change too - this is a recent development. In the past (as recently as 1-2 weeks ago), you could not add more items to a cart than what your inventory would support. For example, if you only have 1 of an item, you could not add 2 or more to the cart - the plus button next to the quantity would gray out.

This must be a recent update - personally, I am not a fan of this. I wish there was a way for Square to ask for feedback before they did these kinds of things. To me, it does not create a good customer experience.

[RencArt]

Indeed, I was sure it was there too! I used it when I was just selling events and workshops on my website and it worked really well.
If they wanted to change it, they could just leave it and make it possible to disable / enable as the customer wishes.

And I agree that it's not the best CX.

[dawnsalvage]

Holy Hell, Thanks so much for explaining. Ive been trying to open my shop for a week but too scared thinking someone was going to order 10 of my one off item! So annoying. Yes they should have two options for this. Pretty easy to do! In the meantime adding a note seems to be my best option.

[RencArt]

Hey there! 😊

Thanks so much for taking the time to explain all this so clearly, that really helps!

That said, it’s honestly surprising (and a bit disappointing) that such a basic functionality isn’t supported out of the box. For a global e-commerce platform like Square, not being able to limit quantity directly on the product page feels quite weird.

I really appreciate the suggested workarounds, sincerely thank you. 🙏
But in our case, they do make our chic gallery look a bit less polished, which is a shame given the kind of exclusive, one-of-a-kind pieces we feature.

Hopefully Square considers adding this soon, it would make a world of difference for shops like ours!

Warm regards,

[Stacelyn24]

Totally agree…drop this in the feature request and if enough people vote they will start working and implementing this feature.  But also…drop your website so we can check out your store 🙂

[RencArt]

Totally! I just did, it’s such a basic feature, I really hope it gets prioritized soon.
And absolutely, here’s the website (still under construction, usuallypassword protected, but I opened it for tonight): www.renc-art.ca 😊
Facebook : https://www.facebook.com/rencart.qc/

Instagram : https://www.instagram.com/rencart.qc/

It’s a boutique-gallery based in Quebec City that features unique pieces of art from local and international artists and craftsmen. Would love to hear your thoughts!

[LittleTreeStudi]

Yes I'm having the same issue at https://shop.littletree.studio/

[LittleTreeStudi]

I hope this is changed soon. Customers get disappointed at checkout when they can't get what they think they could order. Being Chistmas this is a huge issue and does not leave custmmers feeling good about there shopping experince. Please fix this Square.