B2B contact database plus sales engagement and AI prospecting platform.
Instantly.ai vs Seamless.AI
Features, pricing, strengths and trade-offs — and which one fits your situation.
The verdict
Summary
Instantly.ai is best for agencies and founders scaling cold email across many sending accounts, while Seamless.AI is best for sales reps who mainly need verified emails and mobile numbers for prospecting. Only Instantly.ai offers built-in CRM. Seamless.AI has a free plan, while Instantly.ai has no free plan.
Which should you choose?
Choose Instantly.ai if…
- You need agencies and founders scaling cold email across many sending accounts
- Built-in CRM matters to you
- You're one of: lead generation agencies, startup founders doing outbound, sdr teams sending high-volume cold email
- Flat pricing that does not charge per mailbox
Choose Seamless.AI if…
- You need sales reps who mainly need verified emails and mobile numbers for prospecting
- You're one of: sdrs doing phone prospecting, recruiters, sales teams needing contact enrichment
- You want a free plan (Instantly.ai doesn't have one)
- Large database with many mobile numbers
At a glance
| Instantly.ai | Seamless.AI | |
|---|---|---|
| Best for | Agencies and founders scaling cold email across many sending accounts | Sales reps who mainly need verified emails and mobile numbers for prospecting |
| Free plan | No | Yes |
| Starting price | From $47/mo | From $147/mo |
| Learning curve | Low | Low |
| Platforms | Web, Chrome extension, API | Web, Chrome extension, API |
| Ideal for | Lead generation agencies, Startup founders doing outbound, SDR teams sending high-volume cold email | SDRs doing phone prospecting, Recruiters, Sales teams needing contact enrichment |
Feature comparison
| Instantly.ai | Seamless.AI | |
|---|---|---|
| B2B contact database | 450M+ contacts | 1.3B+ contacts |
| Email sequences | Yes | Limited |
| Email warm-up | Yes | — |
| Unlimited sending accounts | Yes | — |
| LinkedIn steps | No | Chrome extension (prospecting only) |
| Built-in CRM | Yes | No |
| AI personalization | Yes | Yes |
| Dialer / calling | Via Instantly CRM | Yes |
| Email verification | Yes | Yes |
IncludedLimited / higher plansNot available— Not confirmed
Security & enterprise
| Instantly.ai | Seamless.AI | |
|---|---|---|
| Business / enterprise plan | Yes | Yes |
| SSO (SAML / OIDC) | — | Yes |
| SCIM user provisioning | — | — |
| SOC 2 | Type I | Type II |
| ISO 27001 | — | No |
| HIPAA (BAA available) | — | — |
| GDPR DPA | Yes | — |
| Data residency options | US (default) | — |
| No training on your data | — | — |
| Audit logs | — | — |
| Admin controls | — | Yes |
| Deployment | Cloud | Cloud |
From each vendor's security documentation. "—" = not confirmed. What to ask vendors · Compare all tools
What each tool does
Instantly.ai
Instantly.ai is a cold email platform built around unlimited sending accounts, automatic warm-up and deliverability tooling. It adds a large B2B lead database, a built-in CRM with calling and SMS, and AI agents for writing, research and reply handling. It is used heavily by lead-gen agencies, startups and outbound teams sending at volume.
Key features- Unlimited email accounts and warm-up on all Outreach plans
- Inbox rotation and deliverability protection
- 450M+ B2B lead database with enrichment and verification
- Built-in CRM with calling, SMS and unified inbox
- AI agents for email writing, web research and replies
- Server and IP sharding on higher plans
Seamless.AI
Seamless.AI is a B2B contact data platform that searches for and verifies emails and phone numbers in real time. It includes a Chrome extension for LinkedIn and company sites, Autopilot for background list building, an AI Writer, and an engagement hub for emailing and calling. It is used by SDRs, recruiters and sales teams focused on phone and email prospecting.
Key features- Real-time contact search with verified emails and mobile numbers
- Chrome extension that overlays contact data on LinkedIn and websites
- Autopilot for automated list building
- AI Writer for cold emails and sales copy
- Buyer intent signals and data enrichment
- Connect engagement hub with emailing, calling and tasks
Pricing
Instantly.ai
No free plan listed; paid from $47/mo (Growth Outreach), 10% off yearly
Seamless.AI
Free plan (50 lifetime credits); Basic ~$147/mo billed yearly; Pro/Enterprise quote-only
Prices last checked September 2026. Plans change often — confirm on each vendor's site.
Pros and cons
Instantly.ai
Strengths- Flat pricing that does not charge per mailbox
- Warm-up network included
- Fast campaign setup with a clean interface
- CRM and lead database available in the same ecosystem
- No native LinkedIn steps inside sequences
- Lead database, CRM and outreach are billed as separate products
- Contact upload limits on lower plans
- Entry plan has a low monthly email cap
Not ideal for: Teams that rely on LinkedIn touches in the same sequence should consider lemlist or Reply.io.
Seamless.AI
Strengths- Large database with many mobile numbers
- Chrome extension fits a LinkedIn-first workflow
- Free plan to test data quality
- CRM enrichment keeps records up to date
- Free plan credits are lifetime, not monthly
- Higher tiers are quote-only and require annual contracts
- Outreach features are basic compared with dedicated sequencers
- Data accuracy complaints are common, so bounce rates vary
Not ideal for: Teams that want sequencing and deliverability tools in the same product should look at Apollo.io or lemlist.
Integrations
Instantly.ai
Seamless.AI
FAQ
What is the main difference between Instantly.ai and Seamless.AI?
Instantly.ai is built for agencies and founders scaling cold email across many sending accounts; Seamless.AI is built for sales reps who mainly need verified emails and mobile numbers for prospecting. Key differences: Instantly.ai offers built-in CRM.
Is Instantly.ai or Seamless.AI cheaper?
Instantly.ai starts from $47/mo and Seamless.AI starts from $147/mo (as of September 2026). On entry price, Instantly.ai is cheaper — but compare what each plan includes, since limits differ. Always confirm current pricing on each vendor's site.
Do Instantly.ai and Seamless.AI have free plans?
Seamless.AI has a free plan, while Instantly.ai has no free plan.
Which is easier to use, Instantly.ai or Seamless.AI?
Both have a low learning curve.
What are good alternatives to Instantly.ai and Seamless.AI?
Other sales & outreach tools worth comparing include Apollo.io, HubSpot and lemlist.
