SquarespaceSquarespace already has a popup. Use it first.
It is built in, it costs nothing extra, and for a site running one offer for everyone it is genuinely enough. This page is about the three specific places it stops — and what to do then.
Three limits, in the order you hit them.
None of these is a criticism — a built-in feature is supposed to be simple.
One popup, site-wide
The built-in promotional pop-up is a single site-level element. You cannot run a different offer on a product page from the one on the blog, or show returning customers something other than the first-visit welcome.
The moment you want two offers, you have outgrown it.
Timing, not behaviour
Native display options are broadly about when and where it appears. There is no exit signal, no cart-value condition, and no reacting to what the visitor has actually done on the page.
Firing on arrival is the pattern that both annoys visitors and attracts Google's intrusive interstitial guidance on mobile.
No audience logic
It does not know whether this person already subscribed. Returning subscribers keep meeting the same signup offer, which is the fastest way to make a working popup look broken in your own analytics.
Suppressing existing subscribers is usually the single biggest quality win available.
What a dedicated tool adds.
One script in code injection, then everything below is campaign-level.
7 trigger conditions
Time, scroll depth, three exit signals, and two cart conditions — combined, so a popup can require both engagement and intent before it appears.
6 audience conditions
Including whether someone has already signed up, which is what stops a subscriber being asked twice.
5 gamified first steps
Spin to win, scratch off, mystery box, plinko and micro-commitment — an easier first click than a bare email field.
6 email and SMS providers
Klaviyo, Omnisend, Mailchimp, Attentive, Postscript, Drip — so signups land where the rest of your marketing already lives.
Squarespace popups, answered plainly.
Including whether you need a third-party tool at all.
Yes. Squarespace includes a promotional pop-up you can enable and style from the site's settings, and their own support documentation is the top result for this search for good reason. It collects email addresses, connects to their mailing list features, and for a site that wants one offer shown to everyone it is genuinely sufficient. Start there before adding anything.
Three reasons, in the order people usually hit them. You want more than one offer — different campaigns on different pages. You want a behavioural trigger, like firing when someone is leaving or when the cart passes a value, rather than just a delay. Or you want to stop showing the signup form to people who already subscribed. The native popup does none of those, and no amount of styling changes that.
For the built-in one, enable it in your site settings and style it there. For a third-party tool, you add a small script to the site-wide code injection area, then build and publish campaigns from the tool's own dashboard — no further Squarespace edits, and nothing to re-do when you change template.
Any additional script has a cost; the question is how large. Look for a loader that is small and loads asynchronously so it does not block the page render, and be wary of tools that pull in a full framework. If you want to check rather than trust a claim, run the site through a page-speed tool before and after adding it — that measurement is more useful than any vendor's stated number, ours included.
A script-based popup runs on any Squarespace page, commerce ones included, because it sits in the page rather than in the template. What differs between tools is whether they can react to commerce state — cart contents, cart value — which requires the tool to read that state rather than merely render on top of it.
The one Squarespace already includes, which costs nothing beyond your existing plan and is the right starting point. Among third-party tools, several offer free tiers with branding or volume caps. BetterPopup does not have a free plan — it is paid after a trial — so if free-forever is the requirement, the native popup or a freemium tool is the honest recommendation.