Best 10 Mailing List Programs to Grow Your Contact List

Building an email list in 2025 feels harder than ever. Everyone’s running ads, attention spans are fried, and cookies aren’t the magic targeting bullet they used to be. If you’ve been staring at your analytics dashboard lately wondering why fewer people are sticking around, you’re not alone.

Traffic costs have jumped +19% per visit over the past two years. That means every bounce stings more than it used to. And the frustrating part? It’s not you. It’s not your products and services. It’s the market. Marketers everywhere are feeling the squeeze.

So, what do you do when it’s getting more expensive to get website visitors to your site? You stop bleeding traffic and start keeping it. Retention is where the game is won now — and email marketing is still the single best retention channel out there. In fact, 75.4% of consumers say email is their preferred channel for promotional messages. Translation: people want to hear from you in their newsletter inbox — you just need to capture email addresses first.

That’s where widgets come in — popups, embedded forms, even gamified spin-to-win wheels. They give you the chance to turn visitors into subscribers right at the moment of interest with a high-converting opt-in form or CTA.

And because there are a million mailing list programs out there all promising to grow your email list fast, we decided to cut through the noise. We’ve pulled together 10 of the best free email list builders to use in 2025. These are tools to grow your audience that marketers actually use, tested in real campaigns.

What to look for in a mailing list programs

Before you start downloading random email list building tools, it helps to know what separates a decent builder from one that just clogs up your dashboard. Free doesn’t mean useless — but it usually means trade-offs. Here’s what to watch for when picking the best list building software for your business.

1. Ease of use matters

If you’ve ever opened a tool that made you feel like you needed a PhD just to launch a signup form, you know the pain. A solid tool shouldn’t make you feel like you’re coding in the Matrix. You want a drag-and-drop builder where you can slap together a signup form, mess with the colors, toss in a quick discount as an incentive to sign, and swap out the CTA without needing a tutorial. If it takes you longer than a coffee break to make those changes, it’s probably not worth your time.

2. Features that actually help you grow

Bare minimum, your email list tools should let you spin up some templates, throw in popups, maybe an exit-intent form so you catch people right before they bounce. If the platform doesn’t do at least that, skip it. The nicer ones go further — think segmentation, proper analytics, automated welcome emails, in some cases even a quick way to build a simple landing page without dragging in another app. All of that just makes it easier to grow your list without duct-taping five different tools together.

3. Integrations = less hassle

Most of us aren’t running email campaigns in a vacuum. If you’re an ecommerce store owner, you’ll want seamless integration with Shopify (look for a Shopify app) or WooCommerce plugin. If you’re heavy on social, you’ll want quick connections to your social media accounts. A solid tool should also play nice with your digital marketing stack — CRMs, marketing emails, automation platforms, etc. The more native integrations, the less time you’ll waste on workarounds.

4. Free vs paid: know the limits

Free is awesome, but always read the fine print. Some platforms cap your subscriber list at 500. Others restrict key features (like A/B testing or advanced targeting) to their paid plans. That doesn’t mean the free tier is useless — far from it. Just make sure the limits still let you start building your list effectively before you commit.

5. Best practices you can’t ignore

No matter which email list builder you choose, the basics don’t change. Throw up some pop-up forms or drop in embedded forms to grab those email addresses, but don’t spam people to death. This means that email listing software should let you control how often widgets appear and ensure that pop-ups don’t overlap each other. Focus on user experience — a mobile-optimized design, fast loading, and a clear value exchange. Done right, even free tools can deliver a solid conversion rate.

The perfect tool is the one that makes it easy to generate leads, grow your customer base, and turn new subscribers into long-term subscribers and customers.

Top 10 free email list builders for 2025

Before making this list, we wanted to be fair. So we started by asking our own customers: what tools did you use before Claspo, and why did you switch? That gave us a good starting point — a set of platforms that are genuinely popular but, for various reasons, didn’t fully meet people’s needs. Then we dug deeper: we scrolled through social media where marketers shared their favorite email list-building tools, compared notes, and even asked ChatGPT which services are the most talked about in 2025.

What we found was interesting: many of the tools that dominate the conversation are ESPs or CRM systems. They’re great at sending marketing emails and managing a subscriber list, but their popups and forms are usually just add-ons. And when it comes to truly effective lead generation — capturing email addresses, segmenting subscribers, and actually helping you build your list — ‘bonus forms’ aren’t always enough.

That’s why we’ll start this ranking with Claspo. With all due respect to other platforms, Claspo was built with all kinds of widgets as a core focus. For us, they’re not a side feature — they’re a full-fledged channel for attracting and retaining customers, improving conversion rates, and even driving sales. At the same time, we want to be transparent: the other services on this list are indeed popular and widely used, and we’ll walk through what they offer, how they work, and the terms of their free plans.

Claspo — the best free email listing software

We’ll be upfront — we’re putting ourselves first. Not because it’s our blog, but because Claspo sets a useful benchmark for what a dedicated email list builder can do.

Different approaches to building a list

Some marketers start small: a built-in opt-in form in the footer or a modest click-based popup that opens when someone taps ‘Subscribe to the newsletter’. Others go further, using lead magnets like ebooks, SaaS guides, or even quizzes that recommend the right product and send tips by email. And then there’s gamification, which can be both fun and powerful. One of our users, WHOSE, collected 4,450 emails in just a week with a ‘wheel of fortune’ widget — and 30% of those new subscribers used their discounts to buy. (You can read the full case study on our site.)

Why Claspo stands out

With Claspo, you’re not stuck with just one kind of popup. The drag-and-drop builder and 1,000+ ready-made templates let you spin up just about anything — floating bars, exit-intent surveys, multi-step forms, even gamified widgets or a quick video block. Everything’s already mobile-optimized, so your widgets look clean on any device, and you can tweak the design to match your brand without losing a weekend in the editor.

The fun really starts with targeting. Want to show a ‘Welcome’ opt-in form only to first-time visitors, but a discount code to returning ones? Easy. Need to run a geo-specific deal? Done. If you’re more advanced, you can hook into cookies, JavaScript variables, or even Data Layer events to trigger popups based on real user behavior. And if you’re worried about annoying people, Overlap Protection and Silence Intervals keep the user experience from turning into popup chaos.

On top of that, you get built-in A/B testing, so you’re not guessing which design or CTA works — you can actually see it in the numbers. And integrations? Claspo connects with the big ESP names like Mailchimp, ActiveCampaign, and GetResponse, so new email subscribers slide right into your campaigns without you lifting a finger. If you’re running an online shop, you’ll also love our WordPress and WooCommerce plugin, along with a Shopify app — making it easy for ecommerce stores to plug Claspo right into their stack without developer help.

Free plan that actually works

Here’s the kicker: all of the above (and much more honestly) comes in Claspo’s Free lifetime plan — one site, up to 30,000 pageviews monthly, and three widgets running at once. And unlike many free email lead lists tools, we don’t limit you to ‘basic’ widget types. You get access to the same features as paid users, so you can start building your list and growing your customer base right away.

Best for

Ecommerce stores, SaaS projects, bloggers, and anyone serious about using email list programs for more than just collecting addresses — whether you’re promoting sales, upselling, cross-selling, gathering feedback, or just getting your first subscriber list off the ground.

Mailchimp — mailing list programs classic

Mailchimp has been around long enough to become the ‘household name’ of popular email marketing platforms. While most people know it for newsletters, automations, and campaigns, it also doubles as an email list building tool. From the audience dashboard, you can dive into the form builder to create a basic email signup form with confirmation pages and a final welcome email.

Mailchimp’s form builder comes with three tabs — Build it, Design it, Translate it. Think of them as three different toolboxes you can flip between. One’s for adding fields and structure, one’s for making it look decent (colors, fonts, layouts), and the last one’s for swapping the default text into another language. Handy if you’re running campaigns outside your home market and need to personalize a web form without paying for a translator. You can also drop in extra fields if you want more than just an email signup — things like names, company, or other contact details that help you grow your contact list.

On the free plan, you’re looking at 500 contacts and 1,000 email sends a month. It does slap the Mailchimp logo on everything and you only get one seat, so don’t expect enterprise vibes here. But if you’re just trying to build your email list from scratch or run a small subscription experiment, it gets the job done. You’ll just notice pretty quickly where the limits are.

If we had to sum it up, Mailchimp’s free plan is best for smaller shops, or solo creators who don’t want to juggle a few platforms. It keeps popup software and email marketing in one spot, which is convenient — at least until you outgrow the starter plan.

Pros & cons:

Familiar interface and 300+ integrations (including Shopify, WordPress, Canva).
Helps you build a list and run perfect email marketing in one place.
Free plan caps out quickly, and branding can feel restrictive.
There is no gamification and no other effective elements for engagement.

HubSpot — email listing software for growing teams

HubSpot is everywhere — if you’ve been around email marketing long enough, you’ve probably heard someone call it the ‘all-in-one’ tool. The nice part is that the forms are tied directly into their CRM. So every time somebody fills out a web form, their contact details go straight into your contact list instead of getting lost in a spreadsheet. From there, you can slide them into a nurture flow or pass them to sales.

The editor itself is drag-and-drop. You can start from scratch or just grab a ready-made template for an ebook download, an event registration, or a plain old newsletter sign-up. HubSpot gives you plenty of layouts — embedded forms, building landing pages (standalone pages), slide-ins, banners, or popups that catch attention. You don’t have to be a marketing expert to tweak fonts, colors, or customize the form to fit your brand.

Where it gets interesting is the conditional logic. You can shorten forms so people don’t bounce, then add steps later to slowly build an email list without asking for everything up front. That’s a smart marketing strategy if you want an opportunity to engage without overwhelming folks.

The free plan. You get 2 users, 2,000 email sends/month, and HubSpot’s logo on everything. There’s no A/B testing and reports are thin, but you can still send one automated follow-up after each email signup and even set up cookie consent banners. It’s not bad if you just need a quick call to action tool while you figure things out.

Pros & cons:

Built-in CRM means no lead slips through.
Lots of layouts and decent ways to build a form.
No A/B testing and limited data unless you pay.
Branding everywhere — fine for testing, not great for polished content marketing.

Klaviyo — one of the best email list tools for ecommerce

If you hang out in ecommerce forums, you’ll see Klaviyo pop up a lot whenever people ask about the best email capture tools. The reason’s pretty simple — it gives you a bunch of starting points (110+ templates) and a drag-and-drop setup that doesn’t make you want to pull your hair out. You can throw together a popup, a banner, a teaser, or even a multi-step form without spending all afternoon in the editor. Want a splashy way to sign up for your email? The platform includes gamification — though it’s limited to the classic spin the wheel.

Forms can be set to trigger on exit-intent, time delay, scroll depth, or even the number of pages viewed, giving you plenty of opportunities to engage before someone leaves. Collision-avoidance settings keep multiple forms from firing at once, so you won’t overwhelm your subscribers and customers.

Targeting is solid but not ultra-granular. You can target visitors by URL, UTM parameter, or broad geolocation (continents and countries, but not cities). For most marketing strategies, that’s enough to build a list and keep messaging relevant.

The free plan covers up to 250 active profiles and 500 monthly email sends — with Klaviyo branding attached. You also get email support for the first 60 days, which is handy if you’re just starting to use this email lists software and don’t want to feel lost.

Pros & cons:

Strong ecommerce focus with 350+ integrations.
Decent set of triggers and widget formats.
The free plan is tight on volume.
Geotargeting is broad — not ideal if you want city-level precision.

OptiMonk — email listing software with gamification

OptiMonk is one of those platforms you’ll see in roundups whenever people ask how to grow your email list. It looks great at first glance, especially with its ‘hundreds’ of templates, but dig deeper and you’ll notice a lot of duplicates across layouts. So if you’re someone who goes to the template library looking for inspiration, it might feel a bit thin. Still, it’ll help you create a variety of campaigns fast, since the drag-and-drop editor makes setup painless.

You can launch all the usual suspects — popups, sticky bars, fullscreen forms, teasers — plus some fun extras like gamified widgets (spin-to-win, pick a gift, scratch cards). Add in countdowns, product recommendations, or discount codes and you’ve got plenty of ways to engage people.

Triggers cover time delay, scroll depth, exit-intent, and even cart value, which is handy for ecommerce.

The free plan is good: 10,000 pageviews per month, unlimited campaigns and users, and all features included — though your widgets will carry OptiMonk branding.

Pros & cons:

Gamification and dynamic content can quickly build engagement.
Campaign scheduling and A/B testing helps you see what works best.
Template library feels repetitive.
Branding stays unless you pay.

OptinMonster — free email lead lists tool… sort of

OptinMonster often comes up when people swap stories about mailing list tools, though calling it ‘free’ is a bit of a stretch. There’s no real free plan, but if you install the WordPress plugin you get a starter account with 3 campaigns and 500 impression credits. Those credits are yours to keep, but once they’re gone, you’ll need to upgrade if you want your popups to keep showing. So, think of it as a trial rather than a permanent option.

Where OptinMonster shines is usability. The drag-and-drop editor is clean and paired with 700+ templates, so even if your design skills stop at doodling on business cards, you can still target people with a professional-looking popup. For WordPress fans, it also plays nicely with Elementor, which makes tweaking layouts easy.

Features are stacked: lightbox popups, floating bars, slide-ins, fullscreen mats, inline forms, sidebars, and even content lockers for gated content. Add gamification, multi-step flows, countdowns, and Smart Tags for personalization, and you’ve got a pretty robust toolkit.

The catch? Many of the best triggers and targeting options (like exit-intent or UTM-based rules) are locked behind higher-tier plans.

Pros & cons:

Beginner-friendly builder with lots of templates.
Integrates well with major ESPs and CRMs.
‘Free’ version is extremely limited.
Advanced targeting is paywalled.

GetResponse — email list building tool inside a bigger suite

GetResponse isn’t really built around widgets — it’s a full marketing platform first, and an email list building tool somewhere down the line. You do get a free account, but it’s more like a 30-day trial of premium features. After that, things get tricky: popups and forms are only unlocked on the ‘Creator’ plan, which runs about €62/month. That’s fine if you want the whole marketing suite (email automation, funnels, webinars), but overkill if you just need popup software to grow your list.

The editor does what you’d expect. You drag blocks around, drop in a field, and you’ve got a form. You can start from nothing or pick a template if you don’t feel like designing. It covers the basics: popup, fullscreen takeover, slide-in, sticky bar, an embedded form. There are some add-ons too — timers, promo codes, product suggestions. Stuff that makes a plain subscription box feel more like an actual call to action.

Triggers are pretty standard. Set it to show after a few seconds, when someone scrolls down, if they’re about to leave (exit intent), or when they just sit there doing nothing. You can also target people by device type, by country, or by whether they’ve been on your site before. Nothing fancy, but enough to get the job done.

Pros & cons:

Clean editor and layouts make it easy to help you create a campaign.
Nice engagement elements like timers and recommendations.
Widgets hidden behind a pricey plan unless you’re on the trial.
Not ideal if all you need is a lightweight way to quickly build your list.

ActiveCampaign is well known for its automation chops, but if you’re looking at it as one of the best list building software options, temper your expectations. The platform technically lets you add sign-up forms, but they’re very plain. You won’t find engaging extras like gamification, countdowns, or even rich visuals. At best, you’re limited to four layouts: inline forms, floating boxes, floating bars, and a basic modal popup.

The editor is serviceable but barebones. You can adjust fields and colors, but forget about advanced tweaks — no motion effects, no custom close buttons, no stock images, no ways to build interactive experiences. Even mobile optimization is limited, so forms don’t always adapt perfectly across devices.

Where ActiveCampaign does shine is integrations: with 900+ connections, you can easily sync new leads into your CRM or marketing tools. But if your goal is to actually build a list with engaging popup software and personalized targeting, the feature set is thin. There’s no exit-intent, no behavioral triggers, no advanced segmentation rules — just simple forms to capture email signup data and push it into your contact list.

Free plan: only a 14-day trial, after which everything is paid. That’s fine if you’re testing automations, but not great if you’re just after an affordable email list building tool to grow subscribers and customers.

Pros & cons:

Great automation + 900+ integrations.
Form builder is minimal — hard to help you create engaging campaigns.
No A/B testing for forms, only for emails.
Basically no advanced targeting or display controls.

MailerLite — the best email list builder for simple setups

MailerLite is often recommended as a beginner-friendly option, and while it’s not flashy, it does cover the basics of a best email list builder. The free plan gives you room for up to 500 subscribers, 12,000 monthly emails, and unlimited embedded forms and popups — though everything carries the MailerLite logo. You also get 24/7 support during your first two weeks, which can be helpful if you’re new to list building. You’ve got one user seat, and a trial of premium features for 14 days. A/B tests and deeper analytics are only in paid tiers.

Customization is better than you’d expect at this level. You can mess around with fonts, colors, and backgrounds so the sign-up form doesn’t look out of place on your site. It’s not drag-and-drop fancy, but the visual editor gets the job done — you can drop in an image, change the header, and make it feel like part of your brand instead of a random box.

MailerLite also adds some guardrails on the subscription side: things like double opt-in and reCAPTCHA. That way, the people landing on your contact list are more likely to be genuine subscribers and not bots filling out forms for fun. That said, there are no targeting rules or advanced triggers — everyone sees the same form.

Pros & cons:

Unlimited sign-up forms even on the free plan.
Easy to help you create forms that don’t clash with your branding.
No targeting or triggers, so limited opportunity to engage specific visitors.
Advanced reporting and A/B testing require an upgrade.

Omnisend — free email lead lists with gamified extras

Omnisend is best known as an ecommerce automation platform, but its form builder gives you some solid options if you’re hunting for free email lead lists tools. Omnisend doesn’t drown you in options — there are about 20 templates. You pick one, set up a popup or a teaser, and then bolt on extras if you need them. Multi-step forms, a countdown, or that wheel-of-fortune game are there if you want to test them. It’s basically a way to make your call to action less boring.

The editor? Just drag and drop. Not fancy. You move text around, swap a button, add a field, maybe drop in a discount code. Done in a few minutes. It’s straightforward enough that you don’t need design skills to make forms that feel like they belong on your site.

On the targeting side, you can show a form only on a specific product page, trigger it after a set delay, or use exit intent to catch people before they leave. Pair that with segmentation (by visitor behavior or page viewed), and you’ve got a decent opportunity to engage the right subscribers and customers.

Free plan: unlimited active signup forms and fields, but your forms will carry Omnisend branding. You also get reporting and A/B testing to see what works best without upgrading.

Pros & cons:

Easy setup with drag-and-drop + gamification.
Unlimited forms, even free.
Templates are limited compared to other mailing list tools.
Branding stays unless you pay.

The challenge: start list building today, not someday

List building is still the backbone of digital marketing. Algorithms change, ad costs rise, cookies disappear — but your subscriber list is yours to keep. Every new email signup is a direct line to someone who’s already shown interest in what you do.

The tools we covered here all give you different ways to build that list, from simple embedded forms to gamified popups and multi-step flows. Some are better for ecommerce, some for SaaS, some for solo creators. What matters most is that you actually start.

So here’s your challenge: pick one free tool today, start building your list, and watch new subscribers roll in. Don’t overthink it — even a basic form is better than waiting another month for the “perfect” setup.

If you want something that won’t box you in later, Claspo is worth a look. It lets you spin up different widgets, try out new ideas, and tweak them until they actually click with your audience. The main thing is: don’t wait around. Your future self will be glad you didn’t sit on it.