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Free migration from EmailBison, Smartlead and Instantly

Everything we learned from the top 1% of GTM agencies—yours by default

One sequencer for email, LinkedIn and calling. Land in the inbox, turn replies into meetings, and let agents run the rest.

Book a callSee how we compare
LinkedInAgentsRolesPortalMeetingsWaterfallMCPIPsAPISlackAnalyticsDataInboxesCRMDomainsWarmupUniboxDialerInMailEmailCalling
Cold outreach

Start more conversations from the first Send⌘↵

Email, LinkedIn and calling in one sequencer, with the deliverability and data top agencies stitch together from five tools.

01 / 03

Isolated IPs per workspace

Most sequencers don't isolate. Good ones isolate per organization. We isolate every workspace.

Warm replies

Turn more replies into booked meetings

The best agencies answer every warm reply fast, on every channel. One thread holds the whole conversation, so nobody asks for context and nothing slips.

  1. Email · LinkedIn

    A master inbox that misses nothing

    Built in · no separate inbox tool
    • Every inbox, email and LinkedIn chat in one Unibox
    • Replies labelled for you: Interested, Meeting, Out of office
    • Interested replies become tasks, so none sit unanswered
    • A reply on any channel stops the sequence everywhere
  2. Agent

    An agent that books the meeting

    Built in · no separate AI reply tool
    • Trained on your website, docs and a playbook per reply type
    • Offers real open times, never the same slot to two leads
    • Sends when it's confident, otherwise drafts for you
    • Drafts land in Slack; CCs your AEs in rotation
  3. Call

    Warm calls in one click

    Built in · no separate dialer
    • Number from their signature, or found with Airscale
    • Calls go out from a local number you own
    • Recorded, transcribed and summarised in the thread
    • Voicemail drops, and callbacks ring the rep who called
Agents

Anything you can do, you can do with an agent

Top agencies run lean because agents handle the busywork. Every action in SendingOS is open to agents, ours or yours.

01 / 03

Built-in agent

Describe a campaign in one sentence. It finds the leads, writes the copy and launches.

CRM

Your CRM stays in sync. No extra tools.

Most sequencers stop at the reply and leave you paying for a sync tool, or gluing your CRM on with automation workflows that break the day a field changes.

The usual way
SequencerSync toolCRM

Another subscription

SequencerWebhookWorkflowCRM

Another workflow to babysit

With SendingOS
HubSpotPipedriveGoHighLevel

Built in. No sync tool, no workflows, nothing extra to pay for.

Reply from inside HubSpot

Reps answer the lead right from the contact record; it sends from the original inbox.

The whole thread on the contact

Every email and reply shows on the contact in your CRM, so nobody asks for context.

Replies logged automatically

Each replied thread lands on the contact's timeline, with no field mapping or webhooks.

Clients

Show clients the results without building a portal

Agencies end up vibe-coding dashboards so clients can see what's happening. Analytics and client logins are built in.

01 / 02

Analytics you'd actually show a client

Email, LinkedIn and calls on one page, down to replies by step and response time.

The details

The small things top agencies sweat

New York
Dallas
Phoenix
Los Angeles

Send at 9 AM wherever they are

9 AM in New York is 6 AM in Los Angeles. Every lead gets your email at the hour you picked, in their own time zone.

Hi ,Hi {first_name | there},

Never send “Hi ,” again

Every variable takes a fallback, so a missing first name never reaches a prospect.

Unibox
Campaigns
Inboxes
Billing

Access down to one job

Give a setter the inbox and nothing else, or an integration a key for one job in one workspace. Every seat has two-factor sign-in.

192 inboxes connected

Connect hundreds of inboxes at once

Bulk-connect Google and Microsoft inboxes instead of adding them one by one.

Compare

How we stack up

Compare with
EmailBison
Price
Emails a month1M for $497500k for $599
Email verificationFreeThrough integrations
Inboxes on sign-upFree, yours to keepNot listed
Calling
Warm callingUnlimited, built inNot listed
Power dialerBuilt inNot listed
Calls in the same thread as email and LinkedInOne threadNot listed
Spam Likely checks on your numbersDaily, iPhone + AndroidNot listed
Pickup predictionScored before you dialNot listed
LinkedIn
LinkedIn sequencerNativeNot listed
Agents
Agent that builds and launches campaignsFrom one sentenceNot listed
Agent you talk to in SlackAgent SendyNot listed
MCP and CLIOfficial MCP + CLIAPI only
Data
Waterfall enrichmentBuilt inThrough paid Clay
AI and HTTP columnsBuilt inThrough paid Clay
Deliverability
Isolated IPsEvery workspaceDedicated IPs
Warmup poolGoogle + Microsoft only, no open sign-upsPrivate, takes approved custom SMTPs
Support
SupportPrivate Slack channelPrivate Slack channel
MigrationDone for youDone for you

Based on each vendor's public pricing and docs, October 2026. “Not listed” means we couldn't find it there. Spotted something out of date? Tell us and we'll fix it.

Pricing

One plan. Everything else free or at cost.

We price the extras to cover what they cost us, not to make money on them.

$497/mo1,000,000 emails a monthBook a call
  • EmailsIncluded in the plan1M a month
  • Email verificationFree
  • Phone numbersUnlimited minutes$1/mo each
  • Spam Likely detectionOn every number you ownFree
  • LinkedIn seatsYour first 3 are free$10/mo each
  • Waterfall enrichmentPer verified phone / email, through Airscale$0.10 / $0.005
  • Database searchesFree
  • AgentsBring your own AI keyFree
  • AI copywriterFree
Limited pre-launch offer
Start sending without paying extra for inboxesSign up before launch and they’re yours to keep. No other sequencer gives you inboxes when you sign up.Free
50 Google inboxesUp to 1,250 emails a day
200 Microsoft inboxesUp to 400 emails a day
One LinkedIn avatarUp to 20 invites and 50 messages a dayFree
Migration

“But man, moving to another sequencer sounds like a lot of work!”

Said every customer ever, all of whom are glad they did it.

Stuck on something? A real person on our team picks it up.
  1. 1

    Connect your old tool

    Paste an API key from EmailBison, Smartlead or Instantly.

  2. 2

    We move everything

    Workspaces, inboxes, campaigns and leads come over automatically, however many and however big. Our team handles anything the API can’t.

  3. 3

    Campaigns resume

    Leads mid-sequence continue from their next step. New leads keep coming in.

Hi, I’m Karim.

Before SendingOS I built Slicey, warmcalling.ai and Itsbetterblue, and worked closely with the agencies that ran on them. Some grew past $1M ARR, two past $10M, others stalled or shut down. You’d recognise a lot of them.

The ones that won did two simple things better than anyone: they sent more outbound to get more replies, and they followed up with every lead, fast and everywhere, to turn those replies into meetings.

Doing that today means stitching ten tools together: a sequencer, a reply tool, a dialer, LinkedIn seats, an enrichment subscription. Then you pay for one more tool whose only job is copying replies into your CRM, a monthly bill for something that should be a checkbox. It adds up to thousands a month, and that’s the cheap part.

The expensive part is the glue. The automation that pushes positive replies into your CRM stops firing after an update, and nobody notices for a week. The client dashboard someone vibe-coded breaks on a Tuesday for no reason. Every fix lands on whoever still remembers how it was wired, and while they dig, the leads who replied go cold.

SendingOS is one product, so there’s nothing to glue. Sending, replies, calls, LinkedIn, enrichment and your CRM run on the same data, and when something breaks, it’s ours to fix, not yours.

It’s what I wish I’d had while scaling to $1M ARR almost on my own. If your stack looks like the one above, book a call and I’ll show you what it looks like as one.

Karim
Karim M · Founder, SendingOS · linkedin.com/in/coldemails
Karim M, founder of SendingOS
FAQ

Questions

Still have a question?Ask the founders on a call. We answer everything, including the awkward ones.Book a call
What does SendingOS cost?

$497 a month, with 1,000,000 emails included. Everything else is either free or priced to cover what it costs us: phone numbers, LinkedIn seats past your first three, and verified enrichment results.

Is the AI agent free?

Yes. Bring your own AI key and the agents, the reply agent and the AI copywriter cost nothing extra on our side. You pay your AI provider directly for what you use, with no markup from us.

How much does enrichment cost?

Database searches are free. Waterfall enrichment runs through our partner Airscale: $0.10 per verified phone number and $0.005 per verified email, and you only pay for results that come back verified.

Is email verification extra?

No. Email verification is free.

What do LinkedIn seats cost?

Your first three LinkedIn seats are free. After that they’re $10 a month each, which covers what they cost us to run.

What does calling cost?

Phone numbers are $1 a month each with unlimited minutes. Spam Likely detection on your numbers is free.

Do I need new inboxes?

No, bring your Google Workspace and Microsoft 365 inboxes with you. And for a limited time before launch, we’re including 50 Google inboxes (up to 1,250 emails a day), 200 Microsoft inboxes (up to 400 a day) and one LinkedIn avatar (up to 20 invites and 50 messages a day) for free.

How long does migration take?

Most of it runs automatically through your current tool’s API, and it’s free. Our team finishes the manual parts, and campaigns resume from where you paused them.

Can my clients see their own results?

Yes. Give each client a login on your own domain, with your logo and colours, showing only their workspace.

Can AI agents run it?

Yes. Use the built-in agent, talk to it in Slack, or connect your own agent over the official MCP server or the CLI.