TL;DR
In early 2026, Cymate's primary email vendor failed and reply rates collapsed across dozens of client campaigns. Rather than wait it out, founder Wesley Hoang ran a head-to-head vendor test. InboxKit came out ahead 2.6x on positive replies — and within three months Cymate had rolled it across their entire client base.
In early 2026, Cymate's primary vendor failed. Reply rates tanked.
For an agency running cold outreach across dozens of clients, that cascades fast: client campaigns fail, clients churn, and each lost $5,000-a-month account costs tens of thousands in lifetime value.
Wesley Hoang, Cymate's founder, knew the fix couldn't wait. In cold email, deliverability is your only product. You test vendors constantly, keep backups in pocket, and switch fast when something breaks.
Deliverability always changes. At some point, we were getting reply rates we didn't want. We tested different vendors. You guys came out on top.
— Wesley Hoang, Founder of Cymate
Cymate didn't switch on a hunch. They ran comparable campaigns side by side on similar send volumes, one on the incumbent vendor and one on InboxKit, and compared what came back.
The incumbent vendor's campaign sent 9,965 emails and returned a 1.14% reply rate — 57 replies, 10 of them positive.
The InboxKit campaign sent a comparable 10,545 emails and returned a 2.47% reply rate — 132 replies, 26 of them positive.
Same agency, same playbook, roughly the same volume. More than double the reply rate, and 2.6x the positive replies.
The test worked. Cymate went all in.
They rolled InboxKit across their entire client base, added it to white label, and automated setup. Three months later: 50 active domains, 150 active mailboxes, and 200+ replies a month.
We did multiple apples-to-apples comparisons and decided to double down on InboxKit and roll it out to pretty much all our customers.
— Wesley Hoang, Founder of Cymate
The recovery showed up where it mattered: in client retention.
For an agency, reply volume isn't a vanity metric. It's the deliverable. When campaigns stall, clients don't wait around for an explanation — they leave. Restoring reply rates across the book meant campaigns that were failing started producing again, and the accounts attached to them stayed.
That's retention instead of churn. That's reputation saved. And it's the difference between defending your existing book and being able to scale it.
Before InboxKit, domain setup meant bouncing between GoDaddy, Porkbun, and Cloudflare, wiring DNS by hand for every new client. InboxKit handles it in one place: domains, mailboxes, SPF/DKIM/DMARC, and warmup, provisioned automatically.
Every time Cymate onboards a new client, infrastructure spins up on its own. White label keeps them in control — they own the client relationship, see each client's deliverability data, and maintain visibility across the whole portfolio.
Every time we have a client onboarding and want new infrastructure, it gets done automatically. You guys handle everything from A to Z.
— Wesley Hoang, Founder of Cymate
For the operational side of running this across many clients at once, our agency workflows guide covers how agencies structure multi-client infrastructure day to day.
Cymate runs done-for-you cold outbound for B2B SaaS. Founded by Wesley Hoang, they've generated over $100 million in closed revenue for clients backed by Y Combinator, Techstars, and First Round Capital.
They handle prospect research, list building, copywriting, deliverability, inbox management, and replies. They're trusted by venture-backed teams because they understand that execution is everything. Learn more at cymate.io.
Running outbound for clients?
InboxKit provides the mailboxes, domains, automated DNS, warmup, and white label options that let agencies recover deliverability fast and keep it stable at scale. See plans and pricing or explore our agency email solution.
Three specialized tools beat any all-in-one platform on deliverability and cost at scale. This is the canonical setup — data, infrastructure, and sending — that powers campaigns at every stage.
Find & verify B2B emails with 94%+ match rates. 300M+ contacts, phone lookup, and validation — clean leads that never burn reputation on bounces.
Explore Enrich
Mailboxes that land in the primary inbox. Automated DNS, warmup, domain isolation, and InfraGuard monitoring across thousands of sending accounts.
Explore InboxKit
Dedicated IPs on every plan, AI warmup that passes ESP detection, inbox placement testing, and a built-in dialer. The deliverability-first sequencer.
Explore SendKitOne compounding system. Enrich feeds verified leads to SendKit, which sends on InboxKit infrastructure.
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Case StudyMost agencies treat client relationships as binary: pay the full retainer or walk. The Playbook Agency built a third option. By reselling InboxKit's infrastructure under their own brand, they gave budget-constrained clients somewhere to land instead of somewhere to leave, cutting churn 80% and growing infrastructure revenue 30%.
Case StudyManaging 100+ client campaigns at scale meant abandoning manual infrastructure work. InboxKit's automation became the only way forward — automated DNS (zero manual hours), domain isolation, zero suspensions, and a 17% average reply rate.
Plans from $39/mo with 10 mailboxes included. Automated DNS, warmup, and InfraGuard monitoring included.
