Outbound OS for Agencies
Stop paying for 8 tools
that don't talk to each other.
NimbusOS replaces your sequences, warmup, enrichment, dialer, and proposals with one contact graph. One login per client. Zero spreadsheet exports.
14-day free trial. Card required to begin. 4 minutes to first client.
The outbound OS that replaces
01
One platform.
Every outbound capability sharing one contact graph.
NimbusOS is the only outbound platform where sequences, warmup, enrichment, dialer, proposals, and AI autopilot operate on the same contact record. When a reply comes in, the autopilot already knows the contact's enrichment tier, warmup stage, and sequence position. No webhooks. No sync delays. No CSV handoffs between tools.
managed inboxes across the warmup pipeline
Source: ReachInbox integration
5 stages
warmup ramp targeting 45 sends per inbox per day at full maturity
Source: email_engine warmup pipeline
02
Your outbound stack is 8 tabs
and a spreadsheet.
Enrichment in one tool. Sequences in another. Warmup somewhere else. Every client handoff is a spreadsheet export. Every suppression list is a manual merge. Every reply signal dies in a tab your team forgot to check. You spend more time moving data between tools than actually selling. And the tools themselves break at scale -- warmup pauses unexpectedly, campaigns fail to send, domains get locked to the platform when you try to leave.
of sales reps feel overwhelmed by their own tools
Source: Kondo State of B2B Sales 2025
cold email infrastructure tools passed a full deliverability audit
Source: Mailforge 2025
03
Every outbound capability. One contact graph.
Built natively. Not bolted together.
MULTI-TENANCY
Agency-native workspaces
Every client gets an isolated workspace. Contacts, sequences, inboxes, and reporting separated by tenant. No cross-client data leaks. No per-seat pricing.
CONTACT INTELLIGENCE
ICP scoring with three engines
Rule-based tier assignment, LLM-powered classification, and composite lead scoring on the same contact record. 41,588 A-tier contacts identified in the current pipeline.
AI AUTOPILOT
RL-trained outbound brain
Reinforcement learning engine adjusts cadence, copy, and channel selection from every reply signal across the platform. It learns from outcomes, not templates.
ENRICHMENT
BYOK -- bring your own API keys
Plug in your own enrichment provider keys. No credit lock-in. No failed lookups burning credits you already paid for. You control costs at the API level.
WHITE LABEL
Your brand, your dashboard
Custom domain, custom logo, client-facing reporting. Run your agency under your own brand without clients seeing the infrastructure underneath.
PROPOSALS
AI proposals with e-signature
Generate proposals from discovery notes. ESIGN Act-compliant signature and Stripe payment built in. No PandaDoc subscription. No switching tools to close.
04
From cold contact to signed proposal in one platform.
Enrich
ICP scoring identifies best-fit accounts across three engines. Phantombuster pulls LinkedIn data. Intent signals flag who is in-market right now.
Sequence
AI generates a personalized opener for every contact. Multi-step sequences launch automatically across 121 managed inboxes with warmup health checks before every send.
Engage
Reply intelligence classifies every response by sentiment and intent. Interested replies trigger the dialer queue and autopilot follow-up. No signal dies in a forgotten tab.
Close
AI generates a proposal from your discovery notes. E-signature and Stripe payment on acceptance. One platform from cold contact to signed contract.
05
What top-performing outbound teams achieve.
Published research. Not our marketing claims.
10-15%+
reply rate for top-quartile cold email teams
Instantly Benchmark Report 2025
2-3x
more replies from personalized vs generic outreach
Hunter.io -- 11M email study
more replies generated by the first follow-up
Belkins 2024
3.7x
more likely to hit quota using AI-native tools
Salesforce State of Sales 2026
Before & After
Manual Setup vs NimbusOS
Every new client means hours of repetitive infra work - unless you automate it.
Manual Setup
~2 to 4 hrs per client
- 1Buy domains one by one15 min
- 2Update nameservers per domain10 min
- 3Set up Cloudflare zone + DNS records20 min
- 4Create email inboxes manually15 min
- 5Connect each inbox to Instantly / Smartlead10 min
- 6Configure warmup settings10 min
- 7Track status in a spreadsheetOngoing
NimbusOS
~4 min per client
- 1Enter client brand name5 sec
- 2Select # of domains + inboxes10 sec
- 3Click "Provision"1 sec
- 4NimbusOS handles everything~4 min
Domains, DNS, inboxes, warmup, and sending tool connection - all automated.
Start your 14-day free trialROI Calculator
How much time are you wasting?
Drag the sliders to match your agency and see the difference.
Per month, every month.
You save
11h 6m
98% less manual work every month
Why NimbusOS
Other tools cover a slice.
NimbusOS covers the full span.
Other outbound tools make you choose: data quality or sending volume, warmup or sequences, personalization or scale. NimbusOS runs every capability on the same contact graph. When enrichment updates a record, the sequence engine already sees it. When a reply signal fires, the autopilot already has the full history.
No lock-in
You own your domains. You bring your own enrichment API keys. No credit systems that penalize you for failed lookups. No domains retained by the platform when you leave.
No per-seat pricing
NimbusOS is $997/month for the first 50 founding members and $1,497/month after that, for the platform, not per user. Add team members without watching your bill scale with every hire. Compare that to $120+/user/month at enterprise tools.
No half-stack
Other tools stop at the reply. NimbusOS continues to the signed proposal: reply intelligence, dialer queue, AI proposal generation, e-signature, and Stripe payment. One system from import to close.
FAQ
Common questions.
What tools does NimbusOS replace?
NimbusOS replaces your email sequencer (Instantly, Smartlead, Lemlist), enrichment tool (Clay, Apollo, ZoomInfo), warmup tool (Lemwarm, Warmbox), dialer (Aircall), conversation intelligence (Gong), and proposal tool (PandaDoc, DocuSign). All capabilities run natively on the same contact graph. One login instead of eight.
Will my deliverability drop if I migrate?
NimbusOS runs a 5-stage warmup ramp across 121 managed inboxes with health scoring and DNS compliance checks. Your inboxes warm up before any campaign volume touches them. We do not start sending until your infrastructure is ready.
How long does onboarding take?
The onboarding flow asks two questions: what sending tool you use today and how many clients you manage. From there, workspaces, sequences, and warmup are pre-configured for your agency size. No 2-week implementation project.
Can I bring my own API keys for enrichment?
Yes. NimbusOS is the only platform in this category that supports BYOK for enrichment providers. Plug in your own keys, avoid credit lock-in, and control costs at the API level.
What does NimbusOS cost?
Founding members get the full platform at $997/month, locked in for life. The founding rate is limited to the first 50 customers; after that the standard rate is $1,497/month. Either way, that is one subscription replacing Instantly, Clay, Apollo, your warmup tool, your dialer, and PandaDoc, with no per-seat pricing.
Your outbound stack should be one platform, not eight tabs and a spreadsheet.
Replace your fragmented GTM stack with one AI-native platform built for agencies.
Running an in-house sales team? See NimbusOS for sales teams