Softwr

E-Commerce · head to head

OpenCart vs Square

OpenCart logo

OpenCart

E-Commerce

Self-hosted open source shopping cart written in PHP, released under the MIT licence

From
Free
Rated
-
Full reviewWebsite
Square logo

Square

E-Commerce

Powering the economy

From
Free
Rated
-
Full reviewWebsite

The short version

  • Each has a real cost: OpenCart extensions modify core behaviour through an XML patching system, so two modules that patch the same file conflict in ways that surface as broken checkout rather than as an installation error, and resolving that requires a developer reading both patches.; Square plus plan pricing not specified in documentation
  • They diverge on capability: OpenCart covers MIT licensed source, Square covers Payment processing.
  • Prices and features above were last checked on 30 August 2026.

Where they differ

Only the attributes on which OpenCart and Square actually diverge.

Attributes where OpenCart and Square differ
AttributeOpenCartSquare
Pricing modelopen-sourcefreemium
PlatformsWebPOS (Mobile app), Web

Identical on both: starting price (Free), free tier (Yes), user rating (Not yet rated), category (E-Commerce), founded (2009).

What each one covers

Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.

Only in OpenCart

  • MIT licensed source
  • Self-hosted PHP and MySQL
  • No transaction fees
  • Multi-store
  • Extension marketplace
  • Multi-currency and multi-language
  • OCMod modification system
  • Full data access

Only in Square

  • Payment processing
  • Point of sale
  • Invoicing
  • Payroll
  • Banking
  • QuickBooks
  • WooCommerce
  • Wix

What people use each for

The jobs each tool is most often brought in to do.

OpenCart

  • A merchant with volume high enough that a percentage transaction fee costs more than a developernot Square
  • An agency building client stores where the client must own the code and the data outrightnot Square
  • A store with unusual catalogue or pricing logic that a hosted platform will not permitnot Square
  • Selling in a market where the local payment gateway is not supported by the mainstream SaaS platformsnot Square

Square

  • Accept payments with all-in-one POS applicationnot OpenCart
  • Online ordering and basic website creationnot OpenCart
  • Invoicing and appointment bookingnot OpenCart
  • Staff scheduling and loyalty programmesnot OpenCart

Where each one falls short

Documented limitations, not opinions. Every one is a constraint you would hit in normal use.

OpenCart

  • Extensions modify core behaviour through an XML patching system, so two modules that patch the same file conflict in ways that surface as broken checkout rather than as an installation error, and resolving that requires a developer reading both patches.
  • Major version upgrades have broken third party extension compatibility, so moving between them means re-purchasing or re-commissioning modules and effectively rebuilding parts of the store rather than clicking update.
  • Hosting, patching, backups and PCI scope are all your responsibility, so a security update you postpone is a breach you own, and there is no vendor obligation to notify or protect you.
  • Extension quality on the marketplace is uneven and modules are sold as one-off purchases with no guaranteed maintenance, so a module central to your store can simply stop being updated and leave you holding the code.
  • The core project is maintained by a very small team relative to the platforms it competes with, so security fixes, compatibility with new PHP versions and feature work all arrive at a pace you cannot influence or pay to accelerate.

Square

  • Plus plan pricing not specified in documentation
  • Processing fees differ by tier but exact rates not detailed
  • Free plan pricing mentioned but specific features for Plus unclear
  • Text marketing charged at 3¢ per message after first 500 included

Pricing, plan by plan

OpenCart

Free
  • Open SourceFree
    • Core ecommerce features
    • Free support
    • Extensions available

Square

Free
  • FreeFree
    • Accept payments with all-in-one POS app
    • Online site builder (ordering profiles, basic websites, online stores, booking sites)
    • Item library and inventory tracking
  • Plus$null/mo
    • All Free plan features
    • Advanced POS features for food, retail, and appointments
    • Lower processing fees on card transactions

Which should you pick?

Choose OpenCart if

  • You need mit licensed source.
  • You want to start without paying.
  • You also want self-hosted php and mysql.
OpenCart review

Choose Square if

  • You need payment processing.
  • You want to start without paying.
  • You work on POS (Mobile app), Web.
  • You also want point of sale.
Square review

Questions people ask

Is OpenCart or Square better?
Neither clearly leads. OpenCart starts at Free and Square at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, OpenCart or Square?
OpenCart starts at Free and Square at Free.
Does OpenCart or Square run on more platforms?
OpenCart runs on Web. Square runs on POS (Mobile app), Web.
Can I use OpenCart for free?
Both have a free tier, so you can try either at no cost before committing.
What is OpenCart best used for?
OpenCart is most often used for a merchant with volume high enough that a percentage transaction fee costs more than a developer, an agency building client stores where the client must own the code and the data outright, a store with unusual catalogue or pricing logic that a hosted platform will not permit, selling in a market where the local payment gateway is not supported by the mainstream saas platforms. Of those, a merchant with volume high enough that a percentage transaction fee costs more than a developer and an agency building client stores where the client must own the code and the data outright are not what Square is typically brought in for.
What can OpenCart do that Square cannot?
OpenCart covers MIT licensed source, Self-hosted PHP and MySQL, No transaction fees, Multi-store. Square covers Payment processing, Point of sale, Invoicing, Payroll.

Answered from the vendors’ own pages

OpenCart: Is OpenCart really free?

The software is MIT licensed with no paid edition. The costs are hosting, extensions, and a developer, and for a low volume store those can exceed a SaaS subscription.

Square: Does Square offer a free plan?

Yes, Square's free plan includes an all-in-one POS app, online site builder, item library and inventory tracking, invoicing, appointment scheduling, staff calendars, and checking and savings account access. No subscription fees are charged.

Source
OpenCart: Does it charge transaction fees?

No. There is no platform cut and no surcharge for using your own payment gateway, which is the main financial argument for self-hosting at volume.

Square: What does Square Plus add compared to the free plan?

Square Plus adds advanced POS features for food and retail, lower processing fees on card transactions, custom loyalty programs, unlimited email marketing campaigns, text messaging, and staff scheduling and attendance tracking.

Source
OpenCart: How hard is customisation?

Theme changes are ordinary PHP templates and are approachable. Changing behaviour means the OCMod patching system, which conflicts between extensions and needs a developer.

OpenCart: What is the biggest hidden cost?

Upgrades. Version transitions have broken extension compatibility before, so budget for a partial rebuild rather than assuming updates are routine maintenance.

Share

Related pages

More on OpenCart

More on Square

Keep looking

Other head to heads