Most SDR teams aren't underperforming because they lack effort. They're underperforming because they're doing manually what should run automatically.
Your reps are spending hours on list-building, data cleaning, personalization, and follow-up timing. That's not selling. That's ops work that a well-built SDR automation system should handle entirely.
This post covers how to build an automated SDR stack using three tools: Clay, HeyReach, and Instantly. What each one does, how they connect, and what the system looks like when it's actually running.
What Is an SDR Automation Stack?
An SDR automation stack is the set of tools and workflows that handle data enrichment, outreach sequencing, and follow-up without requiring manual effort at each step.
It's not a replacement for judgment. It's a replacement for repetitive execution.
A well-built stack covers three layers:
|
Layer |
Function |
Tool |
|
Data & Intelligence |
Enrich, qualify, and score leads |
Clay |
|
LinkedIn Outreach |
Multi-sender sequences, connection requests, DMs |
HeyReach |
|
Email Outreach |
Cold email sequences at scale |
Instantly |
|
Workflow Automation |
Connect tools, route data, trigger actions |
n8n |
Each layer needs to be wired together. If they're operating independently, you don't have a system. You have three separate tools.
Clay: The Intelligence Layer
Clay automation sits at the top of the stack. Before any outreach happens, Clay handles enrichment.
You bring in a list. Clay runs it through 75+ data providers simultaneously to fill in the blanks: verified contact info, tech stack, hiring signals, funding data, LinkedIn activity, intent signals. It's the difference between sending a generic sequence to a cold list and sending a targeted message based on what the company just did.
What Clay does in this stack:
-
Pulls leads from LinkedIn Sales Navigator, Apollo, or your own CRM
-
Enriches with real-time signals (job changes, hiring posts, tech installs, funding rounds)
-
Runs AI-generated personalization fields (first lines, company context, pain-specific hooks)
-
Routes enriched leads into HeyReach or Instantly based on defined criteria
The clay automation workflow is essentially: input a lead source, output a fully enriched, personalized, and segmented contact ready for outreach.
This is also where you apply ICP filtering before any message goes out. Bad data in means bad outreach out.
HeyReach: LinkedIn Outbound at Scale
LinkedIn is where most B2B buyers spend time. The problem is that LinkedIn rate-limits individual accounts aggressively. A single sender can connect with roughly 150-200 people per week before hitting limits.
HeyReach solves this by running outbound across multiple LinkedIn sender accounts simultaneously. Instead of one rep hitting 150 connections a week, you're running 10-15 accounts and reaching 1,500+ prospects weekly with coordinated sequences.
What HeyReach handles:
-
Connection requests with personalized notes (populated from Clay)
-
Follow-up message sequences after acceptance
-
Profile view triggers and engagement warmups
-
Unified inbox across all sender accounts
-
Lead routing back into your CRM or via webhook
This is the workflow automation for LinkedIn specifically. You set the sequence logic once. HeyReach executes it across every sender account on the defined schedule.
One important note: sender account quality matters. Warmed accounts with real activity perform significantly better than freshly created ones. That's an ops consideration before you launch any campaign.
Instantly: Cold Email at Scale
Clay automation feeds into Instantly the same way it feeds into HeyReach. The difference is the channel.
Instantly is built for high-volume cold email with deliverability baked in. You connect multiple sending domains, warm them up within the platform, and run sequences that rotate across domains automatically to protect inbox placement.
What Instantly handles:
-
Email sequences with conditional logic (if opened, if clicked, if replied)
-
A/B testing on subject lines and body copy
-
Deliverability infrastructure (warmup, domain rotation, spam monitoring)
-
Reply detection and auto-pause on positive replies
-
Campaign analytics broken out by sequence, sender, and segment
The combination of Clay enrichment and Instantly sequencing means every email that goes out has:
-
A verified deliverable address
-
A personalized first line or company-specific hook
-
A subject line matched to the segment
-
A follow-up cadence that pauses the moment a reply comes in
This is the baseline for automated SDR email operations. Reps shouldn't be manually sending follow-ups or checking who opened what.
For teams running outbound GTM at scale, Instantly is the execution layer for email, the same way HeyReach is for LinkedIn.
How Clay, HeyReach, and Instantly Connect
The tools don't connect themselves. You need a workflow layer, typically n8n or Zapier, to route data between them and trigger actions based on behavior.
A standard workflow looks like this:
-
Lead enters Clay from a source (Sales Nav export, LinkedIn scrape, CRM segment)
-
Clay enriches the record and generates personalization fields
-
Clay pushes verified leads to HeyReach for the LinkedIn sequence and to Instantly for the email sequence
-
HeyReach runs LinkedIn outreach; Instantly runs email in parallel or staggered
-
Replies, accepts, and engagements route back to your CRM via webhook
-
Hot signals (reply, meeting link click, VSL view) trigger rep notification or auto-booking
This is what workflow automation features for scaling SDR teams actually look like in practice. Not a single tool. A system where data flows without manual handoffs.
The full outbound GTM approach still requires human judgment at the reply layer. The automation handles volume and timing. Your reps handle conversations.
What Results to Expect
Results vary by ICP, messaging quality, and list hygiene. But when the stack is running properly:
|
Metric |
Benchmark Range |
|
Email open rate |
35-55% |
|
LinkedIn acceptance rate |
25-40% |
|
Positive reply rate (combined) |
3-8% |
|
Meetings booked per 1,000 contacts |
15-40 |
|
CAC reduction vs. traditional SDR model |
30-60% |
Phi ran this stack for Payoneer's outbound operation. The result was 93 meetings booked and 44 closed deals in four months. For DataTruck, the same infrastructure drove a 97% CAC reduction alongside $0 to $2.5M ARR growth that preceded their $12M Series A.
The numbers are achievable. But they require the system to be set up correctly, the list to be clean, and the messaging to be built for the ICP. None of that happens automatically.
How Phi Consulting Builds This Stack
Phi's outbound GTM pods are built on this exact infrastructure. Clay, HeyReach, Instantly, and n8n run as one operating layer, not as four separate vendor relationships.
The pod handles:
-
ICP definition and list strategy
-
Clay enrichment and personalization setup
-
HeyReach campaign architecture and sender management
-
Instantly domain setup, warmup, and sequence logic
-
n8n workflows to connect all four systems
-
Ongoing optimization based on reply data and booking rates
This is the difference between buying tools and running a system. A full-funnel GTM approach requires the distribution layer to actually function. The automated SDR stack is that layer.
If you're also thinking about how this connects to broader RevOps infrastructure, the answer is: the CRM is the source of truth, and this stack feeds it. Attribution, pipeline reporting, and deal velocity all depend on the outbound data being clean and trackable.
For teams evaluating whether to build this in-house or run it through a pod, the build timeline matters. Standing up this stack from scratch typically takes 60-90 days when done correctly. A pod that already operates on this infrastructure can start producing a pipeline in the first 30.
The Bottom Line
SDR automation built on Clay, HeyReach, and Instantly is not a shortcut. It's an infrastructure decision.
Done right, it replaces 70-80% of the manual work in outbound operations and lets your reps focus on conversations that actually close. Done wrong, it's just high-volume spam with better tooling.
The system works when the data is clean, the messaging is sharp, and the workflow layer is connecting everything properly. That's the part most teams underestimate.
If you want to see how Phi builds and operates this stack for B2B startups, review the case studies or reach out directly.
