Best Website Builder
I test every website builder so you don’t have to. These are my rankings of the best website builders in 2025.
Our work is supported by affiliate commissions. Learn More
By Steve Benjamins | Fact checked by Juhil Mendpara | Updated Jan 3 2025
I’ve used both Squarespace and Shopify for several different websites.
They are both excellent tools, but they have important differences—differences that make giving a binary answer to “Squarespace vs Shopify: Which is Better?” impossible.
Depending on your website goal(s), either platform can be a better choice.
This article will explain key differences between Shopify and Squarespace to help you understand when to use Squarespace and when to use Shopify.
You’ll see the major differences right away as soon as I describe what both platforms are.
Here’s what I would say if I were describing Squarespace to a friend over coffee. Squarespace is a website builder that has:
The third point is especially important when comparing Squarespace to Shopify— because Shopify only powers ecommerce websites while Squarespace powers a variety of websites.
A Squarespace website can be an online store, but it can also be a church website, a portfolio, a blog, a wedding website, and more.
Here’s how I’d describe Shopify:
Here’s the most important thing to understand:
Shopify is just for ecommerce websites, and Squarespace is for all kinds of websites.
So you can build an ecommerce website with Squarespace, but you can also build all other types of websites.
On the other hand, you can only build an ecommerce website with Shopify (well…technically, you can make all types of websites with Shopify, too, but the platform is focused on ecommerce only).
This leads to important differences:
Squarespace has a visual, drag-and-drop page editor. It’s very easy to use.
You can place blocks anywhere on the page (in a predefined grid). It’s superb from a customization point of view, but it also means you have to tweak the mobile version of the website to make it perfect across all devices.
Compared to Squarespace’s editor, Shopify’s WYSIWYG (what you see is what you get) editor is uninspiring.
Shopify’s editor is similar to Microsoft Word— it’s a rich text editor that lets you place images and videos in line with the text. Still, you might need to preview repeatedly to see how the changes look on the actual store.
The published Shopify page adapts to the theme you use.
Squarespace is known for beautiful templates.
They have over 160+ beautiful, modern website templates for all types of websites (one page, ecommerce, portfolio, membership, etc.) and across 17 categories (Photography, Art & Design, Local Business, etc.). [In addition, there are hundreds of third-party, premium templates.]
Almost 30 of them are specifically for selling products. Besides, there are many for selling services. And you can add a store page to other themes as well, though.
Templates are also really easy to customize — you won’t need to edit code ever to make a beautiful Squarespace ecommerce store!
Shopify includes 12 free themes and 165 premium themes, making a total of 177 themes on Shopify Themes. In addition, you can also install thousands of third-party themes.
Customizing your Shopify theme can be hit or miss. Occasionally, you’ll need to edit HTML and CSS code to make your website look like you want to.
Squarespace is easier to use and can work well for small stores — but Shopify has much more sophisticated ecommerce features.
In fact, Shopify is in a different class from Squarespace when it comes to ecommerce. Shopify powers many large ecommerce stores— including Allbirds, Kylie’s Cosmetics, and Gymshark.
Shopify’s main competitors are heavyweight ecommerce builders like BigCommerce, Volusion, Magento, and WooCommerce. And as you can see from Google Trends, Shopify has risen to the top of this market over the last ten years:
Side Note: Google Trends data has nothing to do with the quality of website builders. It just shows what people are searching for, and they’re more interested in Shopify than other ecommerce platforms over the past few years.
Now that you have an overview of Squarespace and Shopify and know the key differences, you might already be leaning toward one platform for making your website.
If you’re still confused or just want to learn more about both platforms’ capabilities, read below as I dissect and compare Squarespace vs Shopify across key aspects.
If you are choosing between Squarespace and Shopify, you are likely wondering about ecommerce.
I choose Squarespace for small stores as it has more than enough ecommerce features to power a small store.
It has subscription payments, custom notifications, taxes, shipping integrations, digital products, inventory management, rich & related product display, product catalog features, point of sale (POS), etc. It also has beautiful, mobile-optimized templates for online stores.
That said, Squarespace is not (and likely never will be) as powerful as Shopify. And that’s by design: Squarespace is for all kinds of websites, and Shopify is just for ecommerce websites — _a master of one in the true sens_e. So Shopify will always have more ecommerce features.
To understand why, first, let’s look at Squarespace Commerce’s features:
Squarespace allows you to add multiple different shipping options.
Moreover, you can manually set charges for each country/shipping zone if you do international shipping.
For example, here, I set different charges for the US and the Rest of the World:
There’s also a local pickup option. So you can allow customers to order online and pick up the order in person.
One feature that goes right alongside shipping is fulfillment. A fulfillment service company stores your products in its warehouse and then prepares and ships them for you.
Note: You need to use an extension for fulfillment on almost all platforms, including Shopify and Squarespace.
If we exclude all the dropshipping extensions, Squarespace has only one fulfillment option: ShipBob. In other words, if you want to use a fulfillment service with your Squarespace store, you HAVE TO use ShipBob.
Now, ShipBob is undoubtedly one of the top ecommerce fulfillment companies, but Squarespace certainly lacks fulfillment partners.
Squarespace stores can accept payments online through Stripe and Paypal. By extension, this means your customers can pay with all major credit cards, Apple Pay, Afterpay, Paypal, and Venmo.
For Squarespace Point Of Sale, i.e., in-person cash and credit card payments, you can use Square hardware and system.
I love that Squarespace doesn’t charge any transaction fee to users on any Squarespace Commerce plan. Of course, there still are credit card processing fees from Stripe and Paypal, but they are pretty standard everywhere.
Shopify, on the other hand, charges a 0.5%-2.0% additional fee if you use a third-party payment processor—more on it in the Shopify Payments section below.
You can set product prices inclusive or exclusive of tax on Squarespace stores.
To set up sales tax:
Besides sales tax, you can also collect VAT or GST if you are on a Squarespace Commerce plan.
Side note: If you upgrade to the TaxJar Professional plan, you can automate sales tax reporting and filing too.
Squarespace has all the basic inventory management features:
Most people refer to selling physical products online when they say “ecommerce.” So, obviously, Squarespace Ecommerce has features for selling physical products - you can allow your visitors to browse your merchandise, add items to their cart, and checkout simply and efficiently.
Besides physical products, you can also sell the following items with Squarespace:
Here is where Shopify shines.
Shopify is the most powerful and intuitive ecommerce platform available.
They have tons of innovative features that reduce the barriers to starting and scaling an online store.
Here are two of the most important features:
Ecommerce websites can have unique needs. And more business needs = more features required. For example, aside from core features, your store may need features for gift wrapping upsell, inventory integrations, product reviews, cross-sell recommendations, a refer-a-friend program, shipping labels, SMS marketing, email flows, chatbot, etc.
Instead of cramming all of these features into the Shopify core, Shopify built out an app store that allows users to add features as they need them.
Shopify’s core includes what most stores need— apps are for more unusual features such as back-in-stock notifications or gift-wrapping upsells.
It’s difficult to overstate just how important the Shopify app store has become. I’ve used the Shopify app store on every Shopify website I’ve ever started.
Shopify was also the first ecommerce website builder to launch an app store— and today, they have over 10x more apps than their competitors. This means a Shopify store can have more features and functionalities than a store made with any other ecommerce platform.
Squarespace’s app store (called Squarespace Extensions) doesn’t even come close to Shopify’s.
Online stores require a payment processor. Most store builders (such as Squarespace) integrate with a 3rd party processor like Stripe or Paypal.
In 2013, Shopify launched Shopify Payments - their own payment processor. For new Shopify users, it meant they could start taking payments immediately — there was no need to integrate with a 3rd party payment processor.
Everything just worked. This is a perfect example of Shopify working to eliminate one more barrier to starting an online store.
Not only does Shopify Payments work flawlessly, but merchants also benefit from it. While payment processors like Stripe charge a fixed 2.9% + 0.30 USD credit card processing fee, Shopify offers as less as 2.4% + 0.30 USD on its high-tier plan and even lower rates on Shopify Plus. This may seem like a negligible difference, but as you scale, it adds up. A big brand on Shopify easily saves hundreds of thousands in processing fees.
Note: Shopify also allows store owners to integrate with other third-party payment processors/providers. You can use any of the 100+ national and international online payment gateways to accept your customer’s payment method of choice. Unfortunately, Shopify charges a fee of 0.5% to 2% on third-party transactions.
In my experience, Shopify’s core ecommerce features are superior to Squarespace in terms of what’s included in the package and ease of use:
Shopify uses many default sales tax rates and updates them regularly, eliminating a lot of setup work. Also, you can always override the default numbers if needed. Besides sales tax, you can also add “Duties and import taxes” for international orders, VAT, GST, and shipping tax.
News: Shopify recently launched its own advanced tax platform, Shopify Tax. It’s not free, but no worries - you’ll always have access to the free legacy tax features we mentioned above; choose Shopify Tax when you absolutely need it.
You can set up general shipping rates and custom shipping rates for your store with Shopify. For local orders, you can set up pickup and local delivery. There’s also an option to enable third-party calculated rates at checkout, i.e., allow Shopify to dynamically add shipping based on charges by FedEx, USPS, UPS, Canada Post, etc.
Moreover, Shopify has tie-ups with top logistics companies to offer you discounts on shipping rates — you can get up to 88% discount on DHL Express, UPS, or USPS.
In 2019, Shopify launched its own fulfillment service called Shopify Fulfillment Network in the US. This means if you are in the US, you can let Shopify manage your end-to-end fulfillment, which includes inventory management, product storage, and delivery. We haven’t personally used it, but we found it’s more expensive than other 3PL or fulfillment services, + it lacks some fundamental features. But, no worries…
Shopify also integrates with many more mature third-party fulfillment services like ShipBob (the only 3PL service on Squarespace), ShipHero, Red Stag Fulfillment, Shipstation, Ship Monk, etc.
Shopify also has the basic inventory features Squarespace does, including adding inventory, updating inventory, and automatically tracking inventory.
On top of that, Shopify has Transfers. Transfers help you track & record incoming inventory (from suppliers to your location as well as between your store locations):
You can also see the history of the transfers for each inventory item.
Unfortunately, Shopify doesn’t alert you if items run out of stock. You’ll need to install an app for it, and it adds to the business cost.
Besides the core features, Shopify has many more pre-built ecommerce features that Squarespace simply doesn’t have. For example, you can:
Like Squarespace, Shopify has features for selling other things online than just physical products. You can sell digital products, appointments (for service business), memberships, consultations, workshops and virtual classes, event tickets, gift cards, and more. Some of these may require you to add an app, though
You can even keep your offline and online sales in sync with Shopify POS - a much more powerful point-of-sale system than Squarespace POS. For comparison, unlike Squarespace, Shopify POS is omnichannel. Your customers can do local pickup, buy in-store & deliver it to the online address, etc. Moreover, you can send email notifications about items they were interested in but didn’t buy in-store.
Squarespace is a great solution for small stores because it has all the fundamental ecommerce features + other features (as you'll discover below) needed to build a beautiful, easily-manageable store quickly.
However, Shopify is the clear winner for making scalable stores. It has a robust platform and an extensive app store through which you can add even the tiniest ecommerce feature needed.
Try Shopify →
One of the primary reasons to choose a website builder like Shopify or Squarespace is templates. Templates decrease development time drastically. When using a website builder, you don’t need to code and build your website from scratch — just choose a pre-made-by-professional template, make some changes to it, and your website is ready!
Here’s how Squarespace templates compare to Shopify themes:
Squarespace is known for beautiful templates. They have 150+ beautiful, modern website templates.
I think they have the best templates of any website builder — which is subjective but not as subjective as some people think. See these examples:
It’s effortless to customize Squarespace templates. For example, to change your website colors, you just edit the Color Palette:
The color palette automatically applies across your entire website.
So what happens if you don’t like how the color is applied? Well, Squarespace lets you make those specific changes, too — if you want to:
Oftentimes, a website builder’s templates correctly represent the use cases the platform is suitable for.
If you look at Squarespace’s ecommerce templates, you’ll never feel they are for large stores: You won’t see mega menus, in-menu promotions, collections above the fold, enhanced search bar, etc. Instead, the focus will be on small catalogs (15-20 items), stories of the store/person selling the items, etc.
In fact, most themes have “Shop” as a section. In comparison, all Shopify theme previews show just ecommerce websites.
In total, 12 free and 165 paid themes are available on Shopify’s theme store. That’s a total of 177 ecommerce-first Shopify themes! The paid themes cost between $140 and $400.
Each theme is fresh, modern, and sophisticated. And each theme follows the UI best practices for ecommerce stores.
There are thousands of Shopify themes created by 3rd party developers.
These themes cost money and rely on the 3rd party developer to provide support, but there are lots of examples of live Shopify stores that look beautiful.
When it comes to 3rd party Shopify themes, there are two classes: verified providers and unverified.
Shopify includes a Customizer tool for customizing themes:
Unfortunately, the Customizer tool can be hit or miss depending on the theme.
You can do basic things like changing the heading size between small, medium, or large or choosing how many columns you want for displaying the products.
However, you’ll need to jump into code to make most changes. For example, the only way to change the navigation text color is to edit the CSS code
*Here’s my rule of thumb:* If you want a custom Shopify theme, you’re not going to be able to do it without jumping into CSS code occasionally or hiring a Shopify theme expert.
Note: This section likely doesn’t concern you.
You can fully customize your Shopify theme or build a whole new theme for your store with Shopify Liquid API. Liquid is a template language created by Shopify. All Shopify themes are built on top of it.
Something like this is not available for Squarespace.
Shopify makes sure you know their themes are for stores of all sizes. For example, they have a filter that allows you to explore themes based on catalog size (an option like 200+ products suggest they have themes for large catalogs):
If you preview their big catalog themes, you’ll find all the core elements required for a successful big store. Let’s look at the latest Impact theme, for example.
Squarespace templates are great for small stores. They are beginner-friendly, beautiful, and very easy to customize.
Shopify has templates for all sizes of ecommerce stores. Shopify themes are complex to customize but are way more flexible. If you have the time and/or budget, your Shopify store can look however you want it to look — to the pixel!
Try Shopify → Try Squarespace →
“Ease of use” is an essential factor to consider when choosing any software product. A product can have all the features, but it can make your life hell if it’s very complex to use.
Between Squarespace and Shopify, Squarespace is easier to use, but Shopify isn’t super-hard either, as you’ll see:
Squarespace has a visual, drag-and-drop page editor.
There are two elements to each page:
Squarespace has a wide selection of content blocks to add to pages— forms, maps, restaurant menus, buttons, audio players, photo galleries, charts, and more.
You just have to click ‘+’ wherever you want to add the block and add it.
Sections stack vertically on your website and contain content blocks.
While you can create a section from scratch, you can also choose from a library of pre-designed sections:
Squarespace has sections for list, gallery, contact form, newsletter, social media, calendar, and more.
Shopify’s editor isn’t as intuitive as the Squarespace editor.
It is similar to Microsoft Word in that it’s a WYSIWYG rich-text editor that lets you place images and videos in line with the text.
Creating layouts within the Shopify editor can be painful. Moving elements can have unexpected results, and adjusting spacing or adding columns is impossible. It’s challenging to build impressive pages with it, especially if you don’t know coding and UI/UX design.
Squarespace wins this easily:
The product editors of Squarespace and Shopify are pretty similar. Both are straightforward to use rich-text editors with sections to add product details (name, description, variations, etc.), product images, pricing, inventory details, organization (add tags and categories), and other elements.
Besides the primary features, both have some extra-yet-useful features:
One thing I don’t like about the otherwise brilliantly designed website builder, Squarespace, is YOU CAN’T PREVIEW PRODUCT PAGE FROM THE PRODUCT EDITOR! To see how your product page looks after you’ve added all the details on the Squarespace product editor, you have to leave it, preview the whole site, and find the product page there.
Shopify’s product editor is better for two reasons:
It’s important to categorize products well, especially as your catalog size increases.
Let’s take a basic example to understand it better: If you sell clothing for both men and women, you must have a men’s and a women’s collection so that both parties don’t see unrelated clothing items.
Collections only get more complex from here — for example, say you sell seasonal clothes, then you should have a “Summer collection,” “Fall collection,” etc.
You can categorize your products on Squarespace with the category and tags you add when adding the product. However, Shopify takes the medal here for offering an automated collection feature.
With Shopify automated collections: You can set selection conditions to automatically add matching products to a Shopify collection. For example, if you want to make a collection containing all items under $50, you just add that condition to the collection. Similarly, you can add up to 60 selection conditions and specify whether products need to meet all conditions or any condition
Any kind of online business, especially ecommerce, needs marketing to achieve business goals. And both Squarespace and Shopify have a suite of marketing features.
Squarespace has features for:
Squarespace enables you to add SEO page titles and descriptions. In addition, you can no-index pages you don’t want to appear on search engines.
Squarespace also creates sitemaps, markup, and clean URLs for your pages automatically.
Overall, Squarespace sites are built for clean indexing by search engines.
You can use Squarespace pop-ups to invite visitors to join the mailing list, announce (promotions, updates, etc.), ask visitors to verify their age, etc.
The announcement bar lets you, well, announce anything - new product updates, company updates, ongoing sales, etc.
BTW, you can edit the pop-ups and announcement bar as you like.
With Squarespace Email Campaigns, you can grow, manage, and engage your email subscribers/customers.
Besides the general notification emails (of order confirmation, shipping, payments, account, etc.), you can make (and automate) segmented and personalized email campaigns for abandoned cart recovery, welcoming new customers, notifying people on the waitlist, requesting product reviews, etc.
Squarespace also has beautiful, responsive, and easy-to-edit email layouts. And you can match the design elements of your emails with your website. For example, you can choose colors from your site palette.
You can also create emails with your existing products, blog posts, and design elements, so your emails stay consistent with your website branding.
For social media sharing and promoting your social pages, Squarespace allows you to add social media blocks anywhere on the website.
Then there are features for social media promotions:
Shopify has basic marketing features pre-installed on the platform: blogging, announcement bar, basic SEO features, etc. On top of that, you can install Shopify’s own marketing apps as needed. Most of them are free or freemium:
Besides, you can run almost any online marketing campaign seamlessly by adding third-party apps from the Shopify app store.
Though Squarespace covers a lot of ground, it's impossible to beat Shopify on the ecommerce marketing features front.
Almost all good apps on the Shopify app store are developed by a team trying to solve problems in their specific vertical. Plus, you have many more options.
Try Shopify → Try Squarespace →
It’s important to monitor your website performance. Knowing how many users are visiting, what they are doing on the site, where they are coming from, where they are leaving, who are taking desired actions, etc., helps you make informed decisions and optimize processes.
Both Squarespace and Shopify have dedicated analytics platforms to showcase all these KPIs. Which one’s better?
Squarespace neatly and categorically showcases all your website and ecommerce data in its Analytics panel.
You can see the overview of everything going on in your website or go through data analytics by:
Commerce :
Acquisition :
Shopify has a mature analytics platform that shows and reports important ecommerce KPIs.
You can see these metrics on the Shopify Analytics overview board: Total sales, Online store session, Returning customer data, Online store conversion rate, Average order value, Total orders, Top products by units sold, Online store sessions by traffic source, Online store sessions by location, Online store sessions by device type, Online store sessions by social source, Sales by social source, Sales by traffic source, Top referrers by sessions, Top landing pages by sessions, and Sales attributed to marketing.
Under its Reports section, you can find in-depth reports on sales, acquisition, orders, profits, and pretty much all dimensions I mentioned above.
Both platforms have a solid analytics platform, so it's a tie here. Plus, you can always enable Google Analytics or similar tools to get additional insights.
Try Shopify → Try Squarespace →
It’s practically impossible for a website-building platform to include all the features business owners need. A couple of main reasons are:
Therefore, allowing third-party plugins is the only practical solution to giving all features the target customers need.
Squarespace has a selective range of third-party apps on its extensions store. Some of the key apps are SPocket for dropshipping, Printful for print-on-demand, Mailchimp for email marketing, 1-800Accountant for bookkeeping, Delighted for customer feedback, Judge.me for product reviews, etc.
I already discussed the Shopify App Store - it’s the most extensive app store of any ecommerce website builder.
It has over 10,000 apps (!) across categories like store design, marketing, conversion, fulfillment, customer service, shipping, etc. I already shared some of its marketing apps above.
Here are some more of the notable Shopify apps: Oberlo for dropshipping (soon to be a part of DSers), PageFly for building landing pages, Klaviyo for email marketing, Smile for rewards & loyalty programs, AfterShip for order tracking, etc.
Shopify wins this round, hands down. 10,000 apps vs 31 apps — it was never a competition!
Try Shopify →
You can edit your website, check performance, and do a lot more with both Squarespace’s and Shopify’s mobile apps. But how do they compare?
Squarespace has a mobile app for both iOS and Android devices.
As they mention on the app opening page, the Squarespace app allows you to create content, manage your store, and grow your business anytime, anywhere (as long you have a smartphone and internet connection, of course).
Though the app is a bit buggy, you can do almost anything with it — including editing your whole website, adding products, checking analytics, keeping an eye on inventory, adding SEO descriptions, and a lot more.
Shopify, too, has an android and an iOS app.
You can set up your store, add products, add apps, make design changes, publish blog posts, see analytics, and pretty much handle your whole business from the Shopify mobile app.
Squarespace's Android app is a bit buggy, but both Squarespace and Shopify apps are similar as far as features and functionalities go.
Try Shopify → Try Squarespace →
Keeping your visitor and customer data safe and your website secure is crucial. And since Shopify and Squarespace are closed platforms, they take care of these security facets for you.
I searched the internet for any news about Squarespace security breaches or hacked Squarespace websites. What did I find? There’s not a single reported case of a hacked Squarespace-built website! (In contrast, look for something similar about WordPress websites, and you’ll find thousands of examples).
Squarespace ensures website and website user protection by:
Also, security researchers can try finding vulnerabilities on the platform and reporting them to Squarespace for bounties.
Shopify is similar to Squarespace in security regards. They add SSL certificates to all stores and have systems in place to avoid security disasters.
One of the biggest threats for a platform like Shopify could be the vulnerabilities third-party apps bring. But fortunately, as long as you install an app from the Shopify app store, you are safe. Shopify has strict security requirements for developers submitting apps.
Both Squarespace and Shopify are closed systems with needed security systems in place. Therefore, your website will be secure with either platform.
Try Shopify → Try Squarespace →
Squarespace and Shopify have expert support executives. They also have comprehensive resources for people seeking answers to common problems. Moreover, they have dedicated forums where you can ask questions to fellow platform users.
They only differ in the timings and channels of one-on-one communication:
Squarespace allows you to email 24/7/365 or live chat Monday-Friday, 4 AM to 8 PM EDT.
Shopify has options for 24/7 live chat, email tickets, and phone support.
Though you may never need to get in touch with the CS team, Shopify wins this round for providing round-the-clock service and more contact options.
Try Shopify →
Depending on where you are in your business journey, this can be the most important factor or the least important factor.
Squarespace has a 14-day free trial and four plans: Personal, Business, Basic Commerce, and Advanced Commerce.
Annual plans:
Learn more about Squarespace pricing.
Shopify has five plans in total: Shopify Lite, Basic, Shopify, Advanced, and Shopify Plus. Each plan includes all major features, unlimited products, unlimited bandwidth, fraud analysis, and support. And all plans come with a 14-day free trial.
Annual plans:
Learn more about Shopify pricing
Comparing Squarespace base-level, no-ecommerce plans with Shopify plans would be unfair. So I am taking Squarespace Commerce plans vs Shopify plans for this comparison.
Both Shopify and Squarespace plans are excellent value for money. On the surface, Squarespace packages look a bit cheaper, but they are only good for small to mid-sized stores — the kind of stores that can be made with a Shopify Basic plan. The expensive Shopify plans can help ecommerce businesses with more than any Squarespace plan.
Try Shopify → Try Squarespace →Besides the Squarespace or Shopify platform cost, you’ll need to pay:
I think there are two good reasons to use Squarespace instead of Shopify:
I tend to choose Squarespace over Shopify when I am building smaller online stores, and I want to be able to control the design myself.
There is one really good reason to use Shopify instead of Squarespace: Shopify is much more powerful.
For example: Shopify has an app store with 7,000+ 3rd party apps that extend your store features. Squarespace has 31 extensions in comparison. Shopify Review: Pros And Cons in 2025
This makes sense, really: Shopify is just for ecommerce websites. Squarespace is for general websites. So Shopify as a company will always be more focused on ecommerce features.
I tend to choose Shopify over Squarespace when I am building a larger, more mature online store. Shopify already powers many large, unique ecommerce stores (example:All Birds, Kylie’s Cosmetics, and MVMT), and I know they’ll be able to handle it.
No. Neither platform has a free plan but both have a 14-day free trial.
Yes, Squarespace is easier to use than Shopify. Squarespace's drag-and-drop editor makes changing anything a cakewalk; I can't say the same thing about Shopify.
Shopify has more depth in its ecommerce features than Squarespace, so there's a lot Shopify can do on the ecommerce front that Squarespace can't. For example, Shopify automatically adds tax data from around the globe; Squarespace can do it only for the US, and that too will require an extension.
Both platforms have pretty similar SEO features, but Shopify has some SEO apps that might give it an edge.
Technically, Shopify plans cost more than Squarespace plans. But from a value for money perspective, both are head-to-head for the audience they target - Squarespace is for stunning websites & small stores, whereas Shopify is for more mature ecommerce businesses.
Artist websites primarily showcase art, and Squarespace has the best templates for showcasing pictures. Plus, Squarespace is a perfectly suitable solution for selling art, which makes it an overall better website builder for artists.
However, if your goals are ecommerce focused, then Shopify is a better solution. For example, if you want to create an art marketplace to sell works of different artists, then go with Shopify.