Agency New Business, Run Through Instantly
Most agencies don't have a pipeline problem — they have a referral dependency problem. Web projects, brand work, content retainers: the work is good, but new business arrives whenever someone happens to mention you. Cold email is how agencies take that back into their own hands, and the stack splits into two layers. Instantly is where the campaigns live: the campaign builder, A/Z variant testing, the Unibox where replies land. ColdRelay is the layer underneath — the secondary domains, mailboxes, and dedicated IPs those campaigns actually send from.
This guide covers how a multi-service agency wires the two together to fill its own roster: provisioning infrastructure on ColdRelay, importing it into Instantly, and structuring campaigns so each one tests a single sharp offer — instead of broadcasting 'we do everything' to everyone.
Why Run Instantly on ColdRelay Infrastructure
Instantly is built for exactly the kind of testing an agency's new-business motion needs — a fast campaign builder, A/Z variants to pit different offers against each other, unlimited email accounts on paid plans so connecting more mailboxes never raises your software bill. What it doesn't do is provision the mailboxes themselves. Instantly connects accounts; it doesn't register domains, configure DNS, or own IP reputation. That's the infrastructure layer's job.
That's where ColdRelay fits. Instead of stretching your agency's own @agency.com domain — the one your client invoices, proposals, and project threads ride on — you provision secondary domains and mailboxes on isolated Azure tenants with dedicated IPs, SPF, DKIM, and DMARC pre-configured, ready in about an hour. There's no warmup waiting period before you can send: warmup runs continuously as part of each mailbox's daily budget, so the campaign you build today can start today.
The pairing is additive, not competitive: ColdRelay is the infrastructure, Instantly is the sending and testing engine on top. You keep Instantly's campaign builder, variant testing, and Unibox — you just feed it mailboxes built to land, kept far away from the domain your clients reply to.
Visit Instantly →Connecting ColdRelay Mailboxes to Instantly
Provision your sending pool on ColdRelay
Order secondary domains that read like your agency without being your agency — variations on your studio name, never the primary domain. ColdRelay supports 100-150 mailboxes per domain, so an agency's typical starting pool of 20-50 mailboxes fits comfortably on a single domain. Everything provisions on isolated Azure tenants with dedicated IPs in about an hour, with SPF, DKIM, and DMARC already configured.
Export credentials as CSV
From the ColdRelay dashboard, export your mailbox list with SMTP/IMAP credentials. The CSV column layout matches what Instantly's bulk importer expects, so a 40-mailbox pool is one upload, not forty manual connections.
Bulk-import via SMTP/IMAP in Instantly
In Instantly, go to Email Accounts → Add New → Bulk Import via SMTP/IMAP and upload the CSV. Because Instantly's paid plans include unlimited email accounts, every mailbox you add is pure capacity — no per-seat math to second-guess.
Cap each mailbox at 2 outbound sends per day
Set the daily campaign limit on each mailbox in Instantly to 2 outbound emails. That mirrors ColdRelay's per-mailbox budget — 4 sends/day total, split 2 outbound + 2 warmup — with warmup handled continuously on ColdRelay's side. Don't stack Instantly's warmup on top; the budget is already spoken for.
Build one campaign per offer, with A/Z variants inside
In Instantly's campaign builder, create a separate campaign for each service-line offer you want to test — and use A/Z variants within each campaign to test the angle. Attach the full mailbox pool to each campaign in rotation: a 30-mailbox pool gives you 60 outbound sends/day to split across the experiments.
The Agency New-Business Playbook on Instantly
Pick one niche offer per campaign — never the whole menu
'Full-service agency' is the weakest cold email an agency can send. Each Instantly campaign should carry exactly one offer aimed at one vertical: website rebuilds for dental groups, brand refreshes for funded fintechs, content retainers for B2B SaaS. The narrower the campaign, the more the reply data actually tells you — and you can run several narrow campaigns side by side from the same ColdRelay pool.
Lead with the case study, not the capabilities deck
Agencies have an asset most cold emailers don't: finished work with numbers attached. Open the sequence with one specific result — 'we rebuilt a clinic chain's site and organic bookings rose 40%' — for a prospect who looks like that client. The follow-up steps go deeper on the same story. A sequence built around one proof point outperforms a sequence built around a service list, every time.
Use A/Z variants to find which service line pulls
Most multi-service agencies genuinely don't know whether web, brand, or content is their strongest cold offer — referrals never generated that data. Instantly's A/Z testing is how you find out: run variants that lead with different service lines against the same vertical, give each variant enough sends to mean something, and read replies-per-variant in Instantly's campaign analytics. The winning offer becomes the campaign; the losers become the archive.
Treat the Unibox as your new-business desk, not a marketing inbox
Replies to an agency's cold email are often half-qualified briefs — 'we do need the site redone, what would that run?' Those deserve a principal's answer within hours, not an SDR template within days. Route Instantly's Unibox to whoever actually scopes and closes work, and move warm replies to a call before the prospect's attention drifts back to their inbox.
Typical Agency New-Business Benchmarks (Instantly + ColdRelay)
| Metric | Benchmark | Notes |
|---|---|---|
| Inbox placement rate | 95%+ | Dedicated IPs and isolated tenants outperform shared Google/Microsoft pools |
| Reply rate on a niched, case-study-led offer | 3-7% | Single-offer campaigns with a relevant proof point; generic full-service pitches run well under 1% |
| Outbound capacity per mailbox | 2/day | 4 sends/day total per mailbox — 2 outbound + 2 warmup |
| Sends needed per A/Z variant before judging | 200-300 | Below that, variant reply differences are mostly noise; budget pool size around the test, not the other way round |
| Time from signup to first campaign live | Same day | ~60 minutes to provision on ColdRelay, plus list and campaign setup in Instantly |
What It Costs: Instantly + ColdRelay
You pay per mailbox per month for the infrastructure, with volume tiers that drop as you scale (see the table below). DNS, dedicated IPs, and isolated Azure tenants are included — and an agency testing offers can start with a modest pool and grow it only after a campaign proves out.
Instantly is billed separately on its own subscription. Because paid plans include unlimited email accounts, adding more ColdRelay mailboxes never raises your Instantly bill — you pay Instantly for the campaign builder, variant testing, and Unibox, per its current plans.
For an agency, the combined cost is a fixed, predictable new-business line item — one infrastructure bill that gets cheaper per mailbox as you scale, one flat software bill. Compare it to what one referred project is worth, and the math usually resolves itself after the first signed client.
| Mailboxes | ColdRelay price / mailbox / month |
|---|---|
| 1–199 | $1.00 |
| 200–999 | $0.85 |
| 1,000–4,999 | $0.70 |
| 5,000+ | $0.55 |
Each mailbox sends 4 emails per day — 2 outbound to prospects + 2 warmup. ColdRelay provisions mailboxes on isolated Azure tenants with dedicated IPs; Instantly handles the sending, sequencing, and inbox rotation on top.
Frequently Asked Questions
Does ColdRelay replace Instantly?
No — they're complementary layers, not competitors. Instantly handles campaigns, A/Z variant testing, sending rotation, and replies in the Unibox. ColdRelay provides the underlying domains, mailboxes, and dedicated IPs that Instantly sends from. An agency uses both: ColdRelay for the infrastructure, Instantly for the sending and testing on top.
Can we send cold email from our main agency domain instead?
You can, but you shouldn't. Your primary domain carries proposals, invoices, and active client threads — outbound reputation risk doesn't belong anywhere near it. ColdRelay provisions secondary domains on isolated Azure tenants with dedicated IPs, so your new-business experiments are completely walled off from the domain your clients actually email.
How many mailboxes does an agency need to test offers properly?
Work backwards from the test. Each mailbox contributes 2 outbound sends/day (of its 4/day total — the other 2 are warmup), and a meaningful A/Z variant wants 200-300 sends before you judge it. A 30-mailbox pool gives 60 sends/day — enough to settle a two-variant test in roughly a week, or to run two single-offer campaigns side by side. Scale the pool once a winning offer earns the volume.
Do we need to warm up the mailboxes before launching our first campaign?
No waiting period. ColdRelay mailboxes run continuous warmup as part of the standard budget — 4 sends/day per mailbox, split 2 outbound + 2 warmup — so campaigns can start the same day infrastructure provisions, about an hour after you order. Just set Instantly's per-mailbox limit to the 2 outbound sends and skip double-warming the same accounts inside Instantly.