How VeriMails Solves This

Real-time signup verification

Integrate VeriMails API into your registration form. Verify each email as the user types or on form submission. Invalid, disposable, and role-based addresses are caught before account creation. Sub-2-second response ensures zero UX friction.

Disposable email blocking

VeriMails detects 10,000+ disposable email domains (Guerrilla Mail, Temp Mail, etc.). Block these at signup to prevent throwaway accounts from cluttering your user base.

API-first design

Built for developers. Clean REST API, structured JSON responses, straightforward authentication. Integrate in an afternoon, not a sprint. Rate limits from 60/min (free) to 600+/min (business) scale with your growth.

Free tier for development and testing

50 free verifications daily — enough to build and test your integration without any cost. No credit card required. Upgrade to paid plans only when you're ready for production volume.

Recommended Workflow

1. Add VeriMails API to your registration endpoint. 2. On email input, call the verify endpoint. 3. Block invalid, disposable, and role-based addresses. 4. Allow valid addresses to proceed with account creation. 5. For catch-all addresses, use probability scores to decide. 6. Periodically bulk-verify existing user emails to clean your database.

Pricing for SaaS

SaaS signup verification volume depends on growth rate. Early-stage: the free tier (50/day = 1,500/month) may suffice. Growing: Pro ($29/mo) covers up to 10,000 verifications. Scaling: Business ($79/mo) handles 50,000/month. API rate limits scale accordingly.

Frequently Asked Questions

Will verification add latency to my signup flow?

VeriMails API responds in under 2 seconds. For most signup flows, this is imperceptible. You can also verify asynchronously — let the user proceed and flag the account if verification fails, sending a re-verification prompt.

Should I block all disposable emails?

For most SaaS products, yes. Disposable emails indicate users who don't intend to engage long-term. However, for privacy-focused products, you might want to allow them. VeriMails lets you decide — we provide the detection, you set the policy.

How do I handle catch-all addresses at signup?

Allow them. Catch-all addresses from corporate domains are often legitimate users. VeriMails' probability scoring can help you flag suspicious ones for manual review without blocking real users from signing up.

What's the cost per user acquisition?

At $0.0029 per verification, even if you verify 3x per user (signup + 2 re-verifications), the cost is under $0.01 per user. Compare that to your CAC — verification is negligible.

Can I use VeriMails with my existing auth provider?

Yes. VeriMails is a standalone API that verifies email addresses. Call it from your backend before or during the auth flow. It works alongside Auth0, Firebase Auth, Supabase, or any custom authentication system.

Related Resources

Last updated: March 2026

Email Verification for SaaS Companies

For SaaS companies, email is the primary communication channel with users — onboarding sequences, password resets, billing notifications, and feature announcements all depend on valid email addresses. Fake signups and invalid emails don't just waste resources; they undermine the entire user communication infrastructure.

The Challenges

Fake signups inflate metrics and waste resources

Free tiers and trials attract bot signups, disposable email addresses, and fake accounts. These inflate your user count, consume onboarding resources, and make it impossible to measure real product-market fit.

Invalid emails break critical transactional flows

When a user signs up with an invalid email, they can't receive verification links, password resets, or billing notifications. This creates support tickets, failed onboarding, and lost revenue from users who can't complete the signup flow.

Transactional email deliverability is sacred

Your transactional emails (password resets, billing) must reach inboxes. High bounce rates from invalid addresses can degrade your sending domain's reputation, causing legitimate transactional emails to land in spam for real users.

Developer experience matters

SaaS teams need an API that's easy to integrate, well-documented, and fast enough for real-time form validation. Complex SDKs or slow response times create friction in the signup flow.

Try VeriMails Free

50 free email verifications per day. No credit card required. See why teams switch to VeriMails.

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