Grow your email list with opt-in forms

A signup form is the simplest way to turn website visitors into email subscribers. In Stacks, any web form can double as an opt-in form: tick one box and every submission is recorded as a consented subscriber, ready for your campaigns. Turn on double opt-in and Stacks will even ask each new signup to confirm by email first.

Before you start

• You'll need permission to manage forms. Web forms are managed by admins and managers — standard team members and view-only users don't see the setting.
• You'll need a website (or landing page) where you can paste an embed snippet, since forms are added to your own site rather than hosted on a public Stacks page.
• To use double opt-in, connect your email sending under Settings → Email first (your own provider API key and a from-address). Without it, Stacks can record the pending signup but can't send the confirmation link.

Step by step

1. Create a web form. In Stacks, open Web Forms and click Create Form. Give it a name like Newsletter Signup — this is both the internal label and the title shown on the form.
2. Pick your fields. Tick the fields you want to collect: First Name, Last Name, Phone, Company, Message. Email is always included and required — it's the field that makes someone a subscriber.
3. Turn it into an email signup form. Scroll to Automation and tick “Email signup form (submission opts the contact into marketing emails)”. Now every contact from this form is recorded as subscribed, and Stacks skips the sales deal it would normally create — a newsletter subscriber isn't a sales lead.
4. Optional: require double opt-in. Tick “Require double opt-in (email a confirmation link before subscribing)”. New signups stay pending and get an email with a confirmation button; they only become subscribed once they click it. Recommended for compliance (e.g. GDPR) and cleaner lists.
5. Set the finishing touches. Add an auto-tag (e.g. newsletter) to segment subscribers, a notification email so you're alerted on each signup, and a success message or redirect. Then click Create Form.
6. Embed it on your site. Open the form again to reveal the Embed Code block. Copy the HTML embed (a styled, standalone form) or the JavaScript embed (loads and submits via AJAX) and paste it into your website. Advanced users can POST straight to the form's API endpoint instead.
7. Watch subscribers roll in. On single opt-in, a submission subscribes the person instantly. On double opt-in, they see an “almost there — check your email” message and become subscribed after confirming. Each person's status appears on their contact record under Email Marketing.

Good to know

• Consent is recorded with provenance. Stacks stores more than a yes/no — it keeps the method (signup form vs. confirmed opt-in), the source form, and the timestamp, so you have a record of exactly how and when each person opted in.
• No double-confirming. If someone who's already subscribed submits a double opt-in form again, Stacks won't email them a redundant confirmation. Someone who previously unsubscribed, though, must reconfirm before they're re-added.
• Only subscribed contacts get campaigns. Pending (unconfirmed) and unsubscribed contacts are automatically excluded from email sends — so double opt-in protects your sender reputation.
• Duplicates are handled. A repeat signup with the same email updates the existing contact rather than creating a second one.
• Built-in spam protection. The public form endpoint is rate-limited to 10 submissions per minute per IP address.
• Manual control too. You can subscribe or unsubscribe any contact by hand from their record, right next to their consent status.

Frequently asked